Marijuana

Description

Marijuana (marihuana), Cannabis sativa L., also known as Indian hemp, is a member of the Cannabaceae or hemp family, thought to have originated in the mountainous districts of India, north of the Himalayan mountains. The herb was referred to as "hempe" in a.d. 1000 and listed in a dictionary under that English name. Supporters of the notorious Pancho Villa first called the mood-altering herb they smoked marijuana in 1895 in Sonora, Mexico. The term hashish, is derived from the name for the Saracen soldiers, called hashashins, who ingested the highly potent cannabis resin before being sent out to assassinate enemies.

Two related species of cannabis are C. ruderalis and C. indica, a variety known as Indian hemp. Indian hemp grows to a height of about 4 ft (1.2 m) and the seed coats have a marbled appearance.

The species C. sativa L. has many variations, depending on the origin of the parent seed and the soil, temperature, and light conditions. These factors also affect the relative amounts of THC (tetra-hydrocannabinol) and cannabidiol, the chemicals present in varying amounts in cannabis that determine if the plant is primarily a fiber type or an intoxicant. Generally the species grown at higher elevations and in hotter climates exudes more of the resin and is more medicinally potent.

Marijuana is a somewhat weedy plant and may grow as high as 18 ft (5.4 m). The hairy leaves are arranged opposite one another on the erect and branching stem. Leaves are palmate and compound, deeply divided into five to seven narrow, toothed and pointed leaflets. Male and female flowers are small and greenish in color and grow on separate plants. Male flowers grow in the leaf axils in elongated clusters. The female flowers grow in spike-like clusters. The resinous blossoms have five sepals and five petals. The male and female blossoms can be distinguished at maturity. The male plant matures first, shedding its pollen and dying after flowering. Female plants die after dropping the mature seeds. Marijuana produces an abundance of quickly germinating seeds. This hardy annual is wind pollinated and has escaped from cultivation to grow wild along roadsides, trails, stream banks, and in wayside places throughout the world. The plant matures within three to five months after the seed has been sown.

History

Marijuana has been cultivated for thousands of years. Cannabis was first described for its therapeutic use in the first known Chinese pharmacopoeia, the Pen Ts'ao. (A pharmacopoeia is a book containing a list of medicinal drugs, and their descriptions of preparation and use.) Cannabis was called a "superior" herb by the Emperor Shen-Nung (2737–2697 b.c.), who is believed to have authored the work. Cannabis was recommended as a treatment for numerous common ailments. Around that same period in Egypt, cannabis was used as a treatment for sore eyes. The herb was used in India in cultural and religious ceremonies, and recorded in Sanskrit scriptural texts around 1,400 b.c. Cannabis was considered a holy herb and was characterized as the "soother of grief," "the sky flyer," and "the poor man's heaven." Centuries later, around 700 b.c., the Assyrian people used the herb they called Qunnabu for incense. The ancient Greeks used cannabis as a remedy to treat inflammation, earache , and edema (swelling of a body part due to collection of fluids). Shortly after 500 b.c. the historian and geographer Herodotus recorded that the peoples known as Scythians used cannabis to produce fine linens. They called the herb kannabis and inhaled the "intoxicating vapor" that resulted when it was burned. By the year 100 b.c. the Chinese were using cannabis to make paper.

Cannabis use and cultivation migrated with the movement of various traders and travelers, and knowledge of the herb's value spread throughout the Middle East, Eastern Europe, and Africa. Around a.d. 100, Dioscorides, a surgeon in the Roman Legions under the Emperor Nero, named the herb Cannabis sativa and recorded numerous medicinal uses. In the second century, the Chinese physician Hoa-Tho, used cannabis in surgical procedures, relying on its analgesic properties. In ancient India, around 600, Sanskrit writers recorded a recipe for "pills of gaiety," a combination of hemp and sugar. By 1150, Moslems were using cannabis fiber in Europe's first paper production. This use of cannabis as a durable and renewable source of paper fiber continued for the next 750 years.

By the 1300s, government and religious authorities, concerned about the psychoactive effects on citizens consuming the herb, were placing harsh restrictions on its use. The Emir Soudon Sheikhouni of Joneima outlawed cannabis use among the poor. He destroyed the crops and ordered that offenders' teeth be pulled out. In 1484, Pope Innocent VIII outlawed the use of hashish, a concentrated form of cannabis. Cannabis cultivation continued, however, because of its economic value. A little more than a century later, the English Queen Elizabeth I issued a decree commanding that landowners holding 60 acres (24 ha) or more must grow hemp or pay a fine. Commerce in hemp, which was primarily valued for the strength and versatility of its fibers, was profitable and thriving. Hemp ropes and sails were crossing the sea to North America with the explorers. By 1621, the British were growing cannabis in Virginia where cultivation of hemp was mandatory. In 1776, the Declaration of Independence was drafted on hemp paper. Both President George Washington and President Thomas Jefferson were advocates of hemp as a valuable cash crop. Jefferson urged farmers to grow the crop in lieu of tobacco. By the 1850s, hemp had become the third largest agricultural crop grown in North America. The U.S. Census of that year recorded 8,327 hemp plantations, each with 2,000 or more acres in cultivation. But the invention of the cotton gin was already bringing many changes, and cotton was becoming a prime and profitable textile fiber. More change came with the introduction of the sulfite and chlorine processes used to turn trees into paper. Restrictions on the personal use of cannabis as a mood-altering, psychoactive herb, were soon to come.

Controversy

The 1856 edition of the Encyclopedia Britannica, in its lengthy entry on hemp, noted that the herb "produces inebriation and delirium of decidedly hilarious character, inducing violent laughter, jumping and dancing." This inebriating effect of marijuana use has fueled the controversy and led to restrictions that have surrounded marijuana use throughout history in many cultures and regions of the world. Cannabis use has been criminalized in some parts of the United States since 1915. Utah was the first state to criminalize it, then California and Texas. By 1923, Louisiana, Nevada, Oregon, and Washington had legal restrictions on the herb. New York prohibited cannabis use in 1927.

In 1937, the federal government passed the Marijuana Tax Act, prohibiting the cultivation and farming of marijuana. This bill was introduced to Congress by then Secretary of the Treasury Andrew Mellon, who was also a banker for the DuPont Corporation. That same year, the DuPont Chemical Company filed a patent for nylon, plastics, and a new bleaching process for paper. The 1937 Marijuana Transfer Tax Bill prohibited industrial and medical use of marijuana and classified the flowering tops as narcotic, and restrictions on the cultivation and use of cannabis continued. Marijuana was categorized as an illegal narcotic, in the company of LSD and heroin, cocaine, and morphine. Illegal use continued. The FBI publication, Uniform Crime Reports for The United States, 1966 reported that 641,642 Americans were arrested for marijuana offenses that year, with as many as 85% of these arrests for simple possession, rather than cultivation or commerce.

In a reversal of the state-by-state progression of criminalizing marijuana that led to the 1937 Marijuana Transfer Tax Bill, there is a movement underway, state by state, to endorse the legalized use of medical marijuana. By 1992, 35 states in the United States had endorsed referenda for medical marijuana. A growing body of scientific research and many thousands of years of folk use support the importance of medical marijuana in treatment of a variety of illnesses, and the economic value of hemp in the textile, paper, and cordage industries has a long history.

The controversy and misinformation persists around this relatively safe and non-toxic herb. The World Health Organization, in a 1998 study, stated that the risks from cannabis use were unlikely to seriously compare to the public health risks of the legal drugs, alcohol and tobacco. And despite thousands of years of human consumption, not one death has been directly attributed to cannabis use. According to Lester Grinspoon, MD, and James B. Bakalar, JD, in a 1995 Journal of the American Medical Association article, "Marijuana is also far less addictive and far less subject to abuse than many drugs now used as muscle relaxants, hypnotics, and analgesics. The chief legitimate concern is the effect of smoking on the lungs. Cannabis smoke carries even more tars and other particulate matter than tobacco smoke. But the amount smoked is much less, especially in medical use, and once marijuana is an openly recognized medicine, solutions may be found."

General use

Every part of the cannabis plant, including buds, leaves, seeds, and root, has been utilized throughout the long history of this controversial herb. Despite persistent legal restrictions and severe criminal penalties for illicit use, marijuana continues to be widely used in the United States, and throughout the world, both for its mood-altering properties and its proven medicinal applications. The conflicting opinions on the safety and effectiveness of cannabis in a climate of prohibition make any discussion of its beneficial uses politically charged. Marijuana has analgesic, anti-emetic, anti-inflammatory, sedative, anti-convulsive, and laxative actions. Clinical studies have demonstrated its effectiveness in relieving nausea and vomiting following chemotherapy treatments for cancer . The herb has also been shown to reduce intraocular pressure in the eye by as much as 45%, a beneficial action in the treatment for glaucoma . Cannabis has proven anticonvulsive action, and may be helpful in treating epilepsy . Other research has documented an invitro tumor inhibiting effect of THC. Marijuana also increases appetite and reduces nausea and has been used with AIDS patients to counter weight loss and "wasting" that may result from the disease. Several chemical constituents of cannabis displayed antimicrobial action and antibacterial effects in research studies. The components CBC and d-9-tetra-hydrocannabinol have been shown to destroy and inhibit the growth of streptococci and staphylococci bacteria.

In 2002, the Dutch government announced that a small trial would begin in the country to study the effects of medical marijuana on patients with multiple sclerosis . After extending the number of participants in the trial, researchers also hoped to add patients with neuralgia and lower back pain to the study.

Cannabis contains chemical compounds known as cannabinoids. Different cannabinoids seem to exert different effects on the body after ingestion. Scientific research indicates that these substances have potential therapeutic value for pain relief, control of nausea and vomiting, and appetite stimulation. The primary active agent identified to date is 9-tetrahydrocannabinol, known as THC. This chemical may constitute as much as 12% of the active chemicals in the herb, and is said to be responsible for as much as 70–100% of the euphoric action, or "high," experienced when ingesting the herb. The predominance of this mental lightness or "euphoria" depends on the balance of other active ingredients and the freshness of the herb. THC degrades into a component known as cannabinol, or CBN. This relatively inactive chemical predominates in marijuana that has been stored too long prior to use. Another chemical component, cannabidiol, known as CBD, has a sedative and mildly analgesic effect, and contributes to a somatic heaviness sometimes experienced by marijuana users.

Before prohibition, cannabis was recommended for treatment of gonorrhea, angina pectoris (constricting pain in the chest due to insufficient blood to the heart), and choking fits. It was also used for insomnia , neuralgia, rheumatism, gastrointestinal disorders, cholera, tetanus , epilepsy, strychnine poisoning, bronchitis , whooping cough , and asthma . Other phytotherapeutic (plant-based therapeutic) uses include treatment of ulcers, cancer, emphysema , migraine, and anxiety .

The United States federal government policy prohibits physicians from prescribing marijuana, even for seriously ill patients because of possible adverse effects, and the disputed belief that cannabis is dangerously addictive. Former U.S. Attorney General Janet Reno warned that physicians in any state who prescribed marijuana could lose the privilege of writing prescriptions, be excluded from Medicare and Medicaid reimbursement, and even be prosecuted for a federal crime, according to a 1997 editorial in the New England Journal of Medicine. Yet in 1996, California passed a law legalizing medical use of marijuana and many other states have introduced similar laws. The debate in the United States over medical use of the drug continues. Some opponents believe that the movement to legalize marijuana for medicinal purposes is led by those who want the drug legalized for recreational purposes.

Preparations

Cannabis extracts, prepared for medicinal application, are prohibited in the United States. Marijuana is ingested by smoking, which quickly delivers the active ingredients to the blood system. The dried herb is also variously prepared for eating. The essential oil consists of beta caryophyllenes, humules, caryophyllene oxide, alpha-pinenes, beta-pinenes, limonene, myrcene, and betaocimene. The oil expressed from the seeds is used for massage and in making salves used to relieve muscle strain.

Precautions

Marijauna is considered a Class I narcotic and its use has been restricted by federal law since 1937. Penalties include fines and imprisonment. The National Commission on Marihuana and Drug Abuse concluded in 1972 that, "A careful search of the literature and testimony of the nation's health officials has not revealed a single human fatality in the United States proven to have resulted solely from ingestion of marihuana."

Research has shown that cannabis acts to increase heart frequency by as much as 40 beats per minute. A study reported by The American Heart Association in February 2000, concluded that smoking marijuana can precipitate a heart attack in persons with pre-existing heart conditions. One hour after smoking marijuana, the likelihood of having a heart attack is four and one-half times greater than if the person had not smoked, according to the research. A 2002 report cautioned that marijuana use during pregnancy cuts the child's birth weight, a possible indication of problems for the unborn child. Early results indicate that pregnant women should avoid using marijuana.

An additional health concern is the effect that marijuana smoking has on the lungs. Cannabis smoke carries more tars and other particulate matter than tobacco smoke.

Side effects

The PDR For Herbal Medicine reports, "No health hazards or side effects are known in conjunction with the proper administration of designated therapeutic dosages." Smoking the herb, however, "leads almost at once to euphoric states (pronounced gaiety, laughing fits)," and "long term usage leads to a clear increase in tolerance for most of the pharmacological effects." The ability to safely operate automobiles and machinery can be impaired for up to eight hours after ingesting the herb. Chronic abuse results in "laryngitis, bronchitis, apathy, psychic decline and disturbances of genital functions," according to the PDR. In early 2002, several published studies showed conflicting results about the effects of long-term chronic use of marijuana on memory and cognitive function. For the most part, however, these effects seem to lessen after use is halted. Further research on the effects of marijuana on memory and how long those effects may last should continue.

Some people may be hypersensitive to marijuana. They may experience paranoia or be allergic or sensitive to the plant. Chronic sinus fungal infections have been linked to chronic marijuana smoking.

Interactions

Marijauna use may mask the perceived effects of alcohol and cocaine when the drugs are consumed together. Marijuana is said to exert a synergistic effect with other medicinal agents. When used with nitrous oxide it may enhance the effect.

Resources

BOOKS

Foster, Steven, and James A. Duke. Peterson Field Guides, Eastern/Central Medicinal Plants. Boston-New York: Houghton Mifflin Company, 1990.

Lust, John. The Herb Book. New York: Bantam Books, 1974.

Magic and Medicine of Plants. The Reader's Digest Association, Inc. 1986.

PDR for Herbal Medicines. New Jersey: Medical Economics Company, 1998.

PERIODICALS

Eidelman, William S., and Eric A. Voth. "Should Physicians Support the Medical Use of Marijuana?" The Western Journal of Medicine 176, no. 2 (March 2002): 76.

Grinspoon, Lester, M.D., and James B. Bakalar, JD. The Journal of the American Medical Association 273, No. 23 (June 21, 1995): 1875–1876.

Kassirer, Jerome P., M.D. "Federal Foolishness and Marijuana." Massachusetts Medical Society, New England Journal of Medicine 336, no. 5 (January 30, 1997): 366–367.

"Marijuana During Pregnancy Cuts Child's Birth Weight" Women's Health Weekly (January 31, 2002): 5.

Pope, Harrison G. "Neuropsychological Performance in Long-Term Cannabis Users." JAMA, The Journal of the American Medical Association (January 16, 2002): 296.

Sheldon, Tony. "Netherlands to Run Trials of Marijuana in Patients with Multiple Sclerosis." British Medical Journal (March 2, 2002): 504.

"Study Links Long-Term Marijuana Use with Memory Impairment." Alcoholims & Drug Abuse Weekly (March 11, 2002): 3.

OTHER

Campaign to Legalize Cannabis International Association. Cannabis Campaigner's Guide, Up-to-Date Chronology of Cannabis Hemp. 2002 [cited January 2003]. <http://www.ccguide.org.uk/chronol.html>.

Deerman, Dixie, RN. The Best Herb You're Not Using That Could Add Years to Your Life! North Carolina: Community of Compassion, 2000.

Goddard, Ian Williams. Proven: Cannabis Is Safe Medicine. 1996 [cited January 2003]. <http://www.ukcia.org/research/safe-medicine.htm>.

Lewin, Louis. Phantastica, Hallucinating Substances, Indian Hemp: Cannabis Indica. 1931 [cited January 2003]. <http://users.lycaeum.org/~sputnik/Ludlow/Texts/phantastica.html>.

Report of the U.S. National Commission on Marihuana and Drug Abuse, 1972. II. Biological Effects of Marihuana, Botanical and Chemical Considerations. 1972 [cited January 2003]. <http://www.druglibrary.org/schaffer/Library/studies/nc/nc1c.htm>.

Report of the U.S. National Commission on Marihuana and Drug Abuse, 1972. History of Marihuana Use: Medical and Intoxicant. 1972 [cited January 2003]. <http://www.druglibrary.org/schaffer/Library/studies/nc/nc1a.htm>.

Taima in Japan. Drug War Facts: Marijuana. 1999 [cited January 2003]. <http://taima.org/drugfacts/mj.htm>.

Clare Hanrahan

Teresa G. Odle

Marijuana

Definition

Marijuana (marihuana) Cannabis sativa L., also known as Indian hemp, is a member of the Cannabaceae or hemp family, thought to have originated in the mountainous districts of India, north of the Himalayan mountains.

Description

The herb was referred to as "hempe" in a.d. 1000 and listed in a dictionary under that English name. Supporters of the notorious Pancho Villa first used the name marijuana in 1895 in Sonora, Mexico. They called the mood-altering herb they smoked marijuana. The term hashish, is derived from the name for the Saracen soldiers, called hashashins, who ingested the highly potent cannabis resin before being sent out to assassinate enemies.

Two related species of cannabis are C. ruderalis, and C. indica, a variety known as Indian hemp. Indian hemp grows to a height of about 4 ft (1.2 m) and the seed coats have a marbled appearance.

The species C. sativa L. has many variations, depending on the soil, temperature, and light conditions, and the origin of the parent seed. These factors also affect the relative amounts of THC (tetra-hydrocannabinol) and cannabidiol, the chemicals present in varying amounts in cannabis that determine if the plant is primarily a fiber type or an intoxicant. Generally the species grown at higher elevations and in hotter climates exudes more of the resin and is more medicinally potent.

Marijuana is a somewhat weedy plant and may grow as high as 18 ft (5.4 m). The hairy leaves are arranged opposite one another on the erect and branching stem. Leaves are palmate and compound, deeply divided into five to seven narrow, toothed and pointed leaflets. Male and female flowers are small and greenish in color and grow on separate plants. Male flowers grow in the leaf axils in elongated clusters. The female flowers grow in spike-like clusters. The resinous blossoms have five sepals and five petals. The male and female blossoms can be distinguished at maturity. The male plant matures first, shedding its pollen and dying after flowering. Female plants die after dropping the mature seeds. Marijuana produces an abundance of quickly germinating seeds. This hardy annual is wind pollinated and has escaped from cultivation to grow wild along roadsides, trails, stream banks, and in wayside places throughout the world. The plant matures within three to five months after the seed has been sown.

History

Marijuana has been cultivated for thousands of years. Cannabis was first described for its therapeutic use in the first known Chinese pharmacopoeia, the Pen Ts'ao. (A pharmacopoeia is a book containing a list of medicinal drugs, and their descriptions of preparation and use.) Cannabis was called a "superior" herb by the Emperor Shen-Nung (2737-2697 b.c.), who is believed to have authored the work. Cannabis was recommended as a treatment for numerous common ailments. Around that same period in Egypt, cannabis was used as a treatment for sore eyes. The herb was used in India in cultural and religious ceremonies, and recorded in Sanskrit scriptural texts around 1,400 b.c. Cannabis was considered a holy herb and was characterized as the "soother of grief," "the sky flyer," and "the poor man's heaven." Centuries later, around 700 b.c., the Assyrian people used the herb they called Qunnabu, for incense. The ancient Greeks used cannabis as a remedy to treat inflammation, earache, and edema (swelling of a body part due to collection of fluids). Shortly after 500 b.c. the historian and geographer Herodotus recorded that the peoples known as Scythians used cannabis to produce fine linens. They called the herb kannabis and inhaled the "intoxicating vapor" that resulted when it was burned. By the year 100 b.c. the Chinese were using cannabis to make paper.

Cannabis use and cultivation migrated with the movement of various traders and travelers, and knowledge of the herb's value spread throughout the Middle East, Eastern Europe, and Africa. Around 100, Dioscorides, a surgeon in the Roman Legions under the Emperor Nero, named the herb Cannabis sativa and recorded numerous medicinal uses. In the second century, the Chinese physician Hoa-Tho, used cannabis in surgical procedures, relying on its analgesic properties. In ancient India, around 600, Sanskrit writers recorded a recipe for "pills of gaiety," a combination of hemp and sugar. By 1150, Moslems were using cannabis fiber in Europe's first paper production. This use of cannabis as a durable and renewable source of paper fiber continued for the next 750 years.

By the 1300s, government and religious authorities, concerned about the psychoactive effects on citizens consuming the herb, were placing harsh restrictions on its use. The Emir Soudon Sheikhouni of Joneima outlawed cannabis use among the poor. He destroyed the crops and ordered that offenders' teeth be pulled out. In 1484, Pope Innocent VIII outlawed the use of hashish, a concentrated form of cannabis. Cannabis cultivation continued, however, because of its economic value. A little more than a century later, the English Queen Elizabeth I issued a decree commanding that landowners holding sixty acres or more must grow hemp or pay a fine. Commerce in hemp, which was primarily valued for the strength and versatility of its fibers, was profitable and thriving. Hemp ropes and sails were crossing the sea to North America with the explorers. By 1621, the British were growing cannabis in Virginia where cultivation of hemp was mandatory. In 1776, the Declaration of Independence was drafted on hemp paper. Both President George Washington and President Thomas Jefferson were advocates of hemp as a valuable cash crop. Jefferson urged farmers to grow the crop in lieu of tobacco. By the 1850s, hemp had become the third largest agricultural crop grown in North America. The U. S. Census of that year recorded 8,327 hemp plantations, each with 2,000 or more acres in cultivation. But the invention of the cotton gin was already bringing many changes, and cotton was becoming a prime and profitable textile fiber. More change came with the introduction of the sulfite and chlorine processes used to turn trees into paper. Restrictions on the personal use of cannabis as a mood-altering, psychoactive herb, were soon to come.

Controversy

The 1856 edition of the Encyclopedia Britannica, in its lengthy entry on hemp, noted that the herb "produces inebriation and delirium of decidedly hilarious character, inducing violent laughter, jumping and dancing." This inebriating effect of marijuana use has fueled the controversy and led to restrictions that have surrounded marijuana use throughout history in many cultures and regions of the world. Cannabis use has been criminalized in some parts of the United States since 1915. Utah was the first state to criminalize it, then California and Texas. By 1923, Louisiana, Nevada, Oregon, and Washington had legal restrictions on the herb. New York prohibited cannabis use in 1927. Despite the restrictions, cannabis use was woven into the cultural and social fabric in some communities, and widespread use persisted, particularly among the Mexican, Asian, and African American populations.

In 1937, the federal government passed the Marihuana Tax Act, prohibiting the cultivation and farming of marijuana. This bill was introduced to Congress by then Secretary of the Treasury Andrew Mellon, who was also a banker for the DuPont Corporation. That same year, the DuPont Chemical Company filed a patent for nylon, plastics, and a new bleaching process for paper. The 1937 Marijuana Transfer Tax Bill prohibited industrial and medical use of marijuana and classified the flowering tops as narcotic, and restrictions on the cultivation and use of cannabis continued. Marijuana was categorized as an illegal narcotic, in the company of LSD and heroin, cocaine, and morphine. Illegal use continued. The FBI publication, Uniform Crime Reports for The United States, 1966 reported that 641,642 Americans were arrested for marijuana offenses that year, with as many as 85% of these arrests for simple possession, rather than cultivation or commerce.

In a reversal of the state-by-state progression of criminalizing marijuana that led to the 1937 Marijuana Transfer Tax Bill, there is a movement underway, state by state, to endorse the legalized use of medical marijuana. By 1992, 35 states in the U. S. had endorsed referenda for medical marijuana. A growing body of scientific research and many thousands of years of folk use support the importance of medical marijuana in treatment of a variety of illnesses, and the economic value of hemp in the textile, paper, and cordage industries has a long history.

The controversy and misinformation persists around this relatively safe and non-toxic herb. The World Health Organization, in a 1998 study, stated that the risks from cannabis use were unlikely to seriously compare to the public health risks of the legal drugs, alcohol and tobacco. And despite thousands of years of human consumption, not one death has been directly attributed to cannabis use. According to Lester Grinspoon, MD, and James B. Bakalar, JD, in a 1995 Journal of the American Medical Association article, "Marihuana is also far less addictive and far less subject to abuse than many drugs now used as muscle relaxants, hypnotics, and analgesics. The chief legitimate concern is the effect of smoking on the lungs. Cannabis smoke carries even more tars and other particulate matter than tobacco smoke. But the amount smoked is much less, especially in medical use, and once marihuana is an openly recognized medicine, solutions may be found."

Purpose

The whole cannabis plant, including buds, leaves, seeds, and root, have all been utilized throughout the long history of this controversial herb. Despite persistent legal restrictions and severe criminal penalties for illicit use, marijuana continues to be widely used in the United States, and throughout the world, both for its mood-altering properties and its proven medicinal applications. The conflicting opinions on the safety and effectiveness of cannabis in a climate of prohibition make any discussion of its beneficial uses politically charged. Marijuana has analgesic, antiemetic, anti-inflammatory, sedative, anticonvulsive, and laxative actions. Clinical studies have demonstrated its effectiveness in relieving nausea and vomiting following chemotherapy treatments for cancer. The herb has also been shown to reduce intra-ocular pressure in the eye by as much as 45%, a beneficial action in the treatment for glaucoma. Cannabis has proven anticonvulsive action, and may be helpful in treating epilepsy. Other research has documented an in-vitro tumor inhibiting effect of THC. Marijuana also increases appetite and reduces nausea and has been used with AIDS patients to counter weight loss and "wasting" that may result from the disease. Several chemical constituents of cannabis displayed antimicrobial action and antibacterial effects in research studies. The components CBC and d-9-tetrahydrocannabinol have been shown to destroy and inhibit the growth of streptococci and staphylococci bacteria.

Cannabis contains chemical compounds known as cannabinoids. Different cannabinoids seem to exert different effects on the body after ingestion. Scientific research indicates that these substances have potential therapeutic value for pain relief, control of nausea and vomiting, and appetite stimulation. The primary active agent identified to date is 9-tetrahydro-cannabinol, known as THC. This chemical may constitute as much as 12% of the active chemicals in the herb, and is said to be responsible for as much as 70-100% of the euphoric action, or "high," experienced when ingesting the herb. The predominance of this mental lightness or "euphoria" depends on the balance of other active ingredients and the freshness of the herb. THC degrades into a component known as cannabinol, or CBN. This relatively inactive chemical predominates in marijuana that has been stored too long prior to use. Another chemical component, cannabidiol, known as CBD, has a sedative and mildly analgesic effect, and contributes to a somatic heaviness sometimes experienced by marijuana users.

Before prohibition, cannabis was recommended for treatment of gonorrhea, angina pectoris (constricting pain in the chest due to insufficient blood to the heart), and choking fits. It was also used for insomnia, neuralgia, rheumatism, gastrointestinal disorders, cholera, tetanus, epilepsy, strychnine poisoning, bronchitis, whooping cough, and asthma. Other phytotherapeutic (plant-based therapeutic) uses include treatment of ulcers, cancer, emphysema, migraine, Lou Gehrig's disease, HIV infection, and multiple sclerosis.

The United States federal government policy prohibits physicians from prescribing marijuana, even for seriously ill patients because of possible adverse effects, and the disputed belief that cannabis is dangerously addictive. U. S. Attorney General Janet Reno warned that physicians in any state who prescribed marijuana could lose the privilege of writing prescriptions, be excluded from Medicare and Medicaid reimbursement, and even be prosecuted for a federal crime, according to a 1997 editorial in the New England Journal of Medicine.

Preparations

Cannabis extracts, prepared for medicinal application, are prohibited in the United States. Marijuana is ingested by smoking, which quickly delivers the active ingredients to the blood system. The dried herb can also be prepared for eating in cookies or other baked goods. The essential oil consists of beta caryophyllenes, humules, caryophyllene oxide, alpha-pinenes, betapinenes, limonene, myrcene, and betaocimene. The oil expressed from the seeds is used for massage and in making salves used to relieve muscle strain.

Precautions

Marijauna is considered a Class I narcotic and its use has been restricted by federal law since 1937. Penalties include fines and imprisonment. The National Commission on Marihuana and Drug Abuse concluded in 1972 that "A careful search of the literature and testimony of the nation's health officials has not revealed a single human fatality in the United States proven to have resulted solely from ingestion of marihuana."

Research has shown that cannabis acts to increase heart frequency by as much as 40 beats per minute. A study reported by The American Heart Association in February 2000, concluded that smoking marijuana can precipitate a heart attack in persons with preexisting heart conditions. One hour after smoking marijuana, the likelihood of having a heart attack is four and one-half times greater than if the person had not smoked, according to the research.

An additional health concern is the effect that marijuana smoking has on the lungs. Cannabis smoke carries more tars and other particulate matter than tobacco smoke.

Although marijuana is less likely than some other drugs to lead to dependence, heavy users may suffer a withdrawal syndrome characterized by anxiety, irritability, chills, and muscle cramps if they stop usage abruptly.

More seriously, marijuana has been linked to the onset or worsening of certain psychiatric conditions, including panic disorder, schizophrenia, and depersonalization disorder. Persons diagnosed with or at risk for these conditions should not use marijuana.

Side effects

The PDR For Herbal Medicine reports, "No health hazards or side effects are known in conjunction with the proper administration of designated therapeutic dosages." Smoking the herb, however, "… leads almost at once to euphoric states (pronounced gaiety, laughing fits)," according to the PDR, while "long term usage leads to a clear increase in tolerance for most of the pharmacological effects." The ability to safely operate automobiles and machinery can be impaired for up to eight hours after ingesting the herb. Chronic abuse results in "laryngitis, bronchitis, apathy, psychic decline and disturbances of genital functions," according to the PDR.

Some people may be hypersensitive to marijuana. They may be allergic or hypersensitive to the plant. Chronic sinus fungal infections have been linked to chronic marijuana smoking.

KEY TERMS

Antiemetic— A drug or herbal preparation given to relieve nausea and vomiting. Marijuana has antiemetic properties.

Cannabinoids— The chemical compounds that are the active principles in marijuana.

Euphoria— An intense feeling of elation or well-being. Many marijuana users experience temporary euphoria.

A team of German researchers reported in early 2004 that marijuana appears to speed up the progression of cancer. If this finding is replicated by other researchers, it would limit the usefulness of marijuana in treating pain and depression in cancer patients.

Interactions

Marijauna use may mask the perceived effects of alcohol and cocaine when the drugs are consumed together. Marijuana is said to exert a synergistic effect with other medicinal agents. When used with nitrous oxide it may enhance the effect.

Resources

BOOKS

Beers, Mark H., MD, and Robert Berkow, MD, editors. "Cannabis (Marijuana) Dependence." Section 15, Chapter 195. In The Merck Manual of Diagnosis and Therapy. Whitehouse Station, NJ: Merck Research Laboratories, 2004.

PERIODICALS

Amtmann, D., P. Weydt, K. L. Johnson, et al. "Survey of Cannabis Use in Patients with Amyotrophic Lateral Sclerosis." American Journal of Hospice and Palliative Care 21 (March-April 2004): 95-104.

Arsenault, L., M. Cannon, J. Witton, and R. M. Murray. "Causal Association between Cannabis and Psychosis: Examination of the Evidence." British Journal of Psychiatry 184 (February 2004): 110-117.

Dannon, P. N., K. Lowengrub, R. Amiaz, et al. "Comorbid Cannabis Use and Panic Disorder: Short Term and Long Term Follow-Up Study." Human Psychopharmacology 19 (March 2004): 97-101.

Haney, M., C. L. Hart, S. K. Vosburg, et al. "Marijuana Withdrawal in Humans: Effects of Oral THC or Divalproex." Neuropsychopharmacology 29 (January 2004): 158-170.

Hart, S., O. O. Fischer, and A. Ullrich. "Cannabinoids Induce Cancer Cell Proliferation Via Tumor Necrosis Factor Alpha-Converting Enzyme (TACE/ADAM17)-Mediated Transactivation of the Epidermal Growth Factor Receptor." Cancer Research 64 (March 15, 2004): 1943-1950.

Simeon, D. "Depersonalisation Disorder: A Contemporary Overview." CNS Drugs 18 (2004): 343-354.

OTHER

Campaign to Legalise Cannabis International Association. Cannabis Campaigner's Guide, Up-to-Date Chronology of Cannabis Hemp. 〈http://www.paston.co.uk/users/webbooks/chronol.html〉.

Center for Cardiovascular Education, Inc. Smoking Marijuana Increases Heart Attack Risk. Heart Information Network. June 14, 2000. 〈http://www.heartinfo.org/news2000/marijuana061400.htm〉.

Deerman, Dixie, RN. The Best Herb You're Not Using That Could Add Years to Your Life! North Carolina: Community of Compassion, 2000.

Goddard, Ian Williams. Proven: Cannabis Is Safe Medicine. 〈http://sers.erols.com/igoddard/hempsafe.htm〉.

Lewin, Louis. Phantastica, Hallucinating Substances, Indian Hemp: Cannabis Indica. 〈http://users.lycaeum.org/∼sputnik/Ludlow/Texts/phantastica.html〉.

Taima in Japan. Drug War Facts: Marijuana. 〈http://taima.org/drugfacts/mj.htm〉.

MARIJUANA

Marijuana is a dried mixture of the leaves and flowers of Cannabis sativa, or hemp plant. Slang words for marijuana include "pot," "weed," "grass," and "dope." The term "cannabis" refers to different psychoactive preparations of the plant, including marijuana, hashish, and hashish oil. Hashish is the resin produced by the flowering tops of the plants; hashish oil is a concentrated form of cannabis extracted from the plant or resin using a solvent. Unpollinated female plants are called sinsemilla (sen-suh-mee-ah) and the flowering tops of these plants produce potent "buds" that do not contain seeds.

The major psychoactive ingredient in cannabis is delta-9-tetrahydrocannabinol (THC), but there are more than sixty related chemicals in marijuana, which are called "cannabinoids." Cannabis also contains other unrelated compounds that have similar psychoactive effects. The World Health Organization reported in 1997 that THC content in marijuana ranges from 0.5 to 4 percent, while concentrations in cannabis oil, hashish, and sinsemilla generally range from 7 to 14 percent, but may be as high as 20 percent. THC concentration depends on the variety, sex, and growing conditions of the plant, and it has increased over the years due to hydroponic cultivation techniques and selective breeding.

Marijuana and other cannabis products are usually smoked as a cigarette (a "joint") or in pipes, but may also be ingested orally. In the 1990s, the use of "blunts" to smoke marijuana became more common. A blunt is made by removing the tobacco from a cigar wrapper and filling it with marijuana, or a mixture of marijuana and some other drug like cocaine.

PSYCHOACTIVE AND PHYSIOLOGICAL EFFECTS

THC is absorbed more quickly into the bloodstream when smoked than when eaten. Effects are felt almost immediately and peak within thirty minutes of smoking. The marijuana "high" results when the THC binds with cannabinoid receptors in the brain. This process slows down regular nerve transmission, interfering with normal function. The cannabinoid receptors are located in the areas of the brain involved in muscle control, sexual functioning, vision and hearing, reasoning, hormone release, and memory.

Short-term effects include a temporary increase in heart rate, blood pressure, and blood flow to parts of the brain. Users generally feel a sense of euphoria, relaxation, hilarity, and heightened sensory perception. Negative psychological reactions may include anxiety, hallucinations, and panic attacks. Many smokers report that they feel unmotivated when they are high. Cannabis intoxication alters perceptions of time and space and impairs reaction time—affecting the performance of psychomotor tasks such as driving, which increases the risk of motor vehicle accidents. Cannabis increases food intake, impairs learning capabilities, and affects short-term memory. Many cannabis effects are subjective and influenced by the social circumstances, but the extent of impairment mainly depends on the potency and dose of the drug, the individual's tolerance to and experience using cannabis, and the difficulty and complexity of the task at hand.

LONG-TERM HEALTH CONSEQUENCES

Many of the studies done on the health consequences of marijuana have been inconclusive, although a picture is emerging of some worrisome long-term health effects. Smoking marijuana affects the respiratory system in much the same way as cigarette smoking. Cannabis smoke contains many of the same toxic chemicals and carcinogens as tobacco, as well as cannabinoids, all of which are respiratory irritants. Frequent marijuana smokers often report laryngitis, hoarseness, and coughing, and they are more likely than infrequent or nonusers to get acute and chronic bronchitis.

In a comprehensive analysis of the health effects of cannabis, the World Health Organization reports that cannabis is known to have adverse effects on the immune system, reproductive system, adrenal hormones, growth hormone, and cognitive function, particularly related to attention and memory processes. The long-term consequences of these effects, however, are not fully known, and further research is warranted. Smoking marijuana during pregnancy reduces oxygen flow to the fetus, which may interfere with growth and result in low birth weight, premature birth, and deficits in verbal ability and memory during childhood.

Preliminary research has demonstrated some positive health benefits of marijuana, including control of nausea and vomiting in people suffering from advanced cancer and AIDS (acquired immunodeficiency syndrome), appetite stimulation for those with wasting diseases, treatment of glaucoma by reducing intraoculer pressure, and control of convulsions and muscle spasms. More research in these areas is needed.

TRENDS IN MARIJUANA USE

Marijuana use by young people in North America peaked at the end of the 1970s, then declined progressively until the early 1990s, when use began to rise again. In the United States, it appears that the rate of increase may have stabilized at the end of the 1990s, although this stabilization was not apparent in Canada. The Monitoring the Future Survey found that lifetime use of marijuana among U.S. high school seniors peaked in 1979 at 60.4 percent, declined to a low of 32.6 percent in 1992, then rose to 49.6 percent in 1997, where it appears to have leveled off. A 1998 Canadian study on marijuana use did not report use among twelfth graders, but did find that approximately 42 percent of tenth graders had used marijuana in the previous year, up from 25 percent in 1991. In comparison, in 1998 only 31.1 percent of tenth graders in U.S. high schools reported use.

Marijuana use across the entire U.S. population was examined in a household survey in 1992 by the National Institute on Drug Abuse, which reported that 33 percent of Americans age 12 years and over had tried marijuana, 9 percent had used it during the previous year, and approximately 4 percent were current users, though the rate of use varied with age. These figures changed little in the 1998 survey. The proportion of Americans who reported having used marijuana at some point in their life was 11 percent among those 12 to 17 years old, 59 percent among those 26 to 34 years old, and 25 percent among people 35 years old and older.

1n 1994, the Canada Alcohol and Other Drug Survey found that 28 percent of Canadians had used cannabis at least once, 7.4 percent used it in the past year, and 3.2 percent were current users. During the early to mid-1990s, the proportion of people in other countries who reported having tried marijuana was 34 percent in Australia, 43 percent in New Zealand, 37 percent in Denmark, 17 percent in Switzerland and 14 percent in the United Kingdom. In general, marijuana use is lower among European, African, Asian, and South American youth than among young people in North America.

Different subgroups in the North American population report different rates of use. In general, males and white youth report higher rates of marijuana use than females, black youth, or young people from other racial or ethnic backgrounds. Young people who have dropped out of school are more likely to use cannabis than those who are in school, and 84.5 percent of students who attended alternative high schools in 1998 said they had tried cannabis.

MARIJUANA AND SUBSTANCE ABUSE

Since the 1970s, research has consistently demonstrated that adolescents progress through a uniform sequence of drug use involvement that begins with alcohol, cigarettes, and marijuana and proceeds to the use of "hard" drugs like hallucinogens, benzodiazepenes, amphetamines, sedatives, cocaine, and heroin. For this reason, marijuana, alcohol, and tobacco have been called "gateway" drugs. Some studies have shown that use of marijuana is almost a necessary condition for cocaine use by youth. The more frequently and intensively that gateway drugs are used, the greater the likelihood of dependence on the drug and progression to a later stage in the sequence of substance use involvement. However, most young people who use marijuana do not progress to dependence, or use harder drugs. The majority of marijuana users do not use other illicit drugs, although they are more likely to smoke cigarettes and drink alcohol than nonusers. Heavy use of marijuana does, however, place users in contact with more diverse networks of drug users and sellers, thereby increasing their exposure to other drugs and to the influence of those who use them. Participation in street culture is related to marijuana use. Those young people who do progress to abuse other illicit drugs and who experience the most harmful consequences are more likely to be socially and economically disadvantaged.

PREVENTION

Most cannabis-use prevention programs are school based, and they tend to focus on illicit drugs in general, not just marijuana. The existence of a stable pattern of drug use suggests that prevention efforts should be directed not only at preventing the initiation of use, but also at curbing the transitions from experimental to regular use of any of the gateway drugs and the transition to other drugs. In reviewing what works in drug-use prevention, D. R. Gerstein and L. W. Green found that no prevention programs were reliably effective in all cases with all groups. However, a number of principles for effective prevention have been identified. The U.S. National Institute on Drug Abuse suggests that programs should be comprehensive and long-term, with reinforcement over several years; should target all forms of drug abuse; focus on the family, with a parent or caregiver component; include interactive methods, and be age-specific, developmentally appropriate, and culturally sensitive. School programs are best offered in the sixth through tenth grade, and should include components to develop interpersonal social skills, resistance skills, and self-efficacy, and to improve knowledge of health effects. The higher the level of risk in the specific population, the more intensive and targeted the program should be.

Marjorie A. MacDonald

(see also: Addiction and Habituation; Behavior, Health-Related; Health Promotion and Education; School Health; Social Determinants; Substance Abuse, Definition of )

Bibliography

Adlaf, E. M.; Ivis, F. J.; Smart, R. G.; and Walsh, G. W. (1995). The Ontario Student Drug Use Survey: 1977–1995. Toronto: Addiction Research Foundation of Ontario.

Ellickson, P. L.; Hays, R. D.; and Bell, R. M. (1992). "Stepping Through the Drug Use Sequence: Longitudinal Scalogram Analysis of Initiation and Regular Use." Journal of Abnormal Psychology 101:441–451.

Gerstein, D. R., and Green, L. W., eds. (1993). Preventing Drug Abuse: What Do We Know? Washington, DC: National Academy Press.

Grunbaum, J.; Kann, L.; Kinchen, S.; Ross, J. G.; Gowda, V. R.; Collins, J. L.; and Kolbe, L. J. (1998) "Youth Risk Behavior Surveillance—National Alternative High School Youth Risk Behavior Survey, United States, 1998." Morbidity and Mortality Weekly Report 48 (SS07):1–44. Available at http://www.cdc.gov/epo/mmwr/preview/mmwrhtml/ss4807al.htm.

Health Canada (1995). Canada's Alcohol and Other Drugs Survey: Preview 1995. Ottawa: Minister of Supply and Services Canada.

Howlett, A. C.; Bidautrussell, M.; Devane, W. A.; Melvin, L. S.; Johnson, M. R.; and Herkenham, M. (1990). "The Cannabinoid Receptor—Biochemical, Anatomical and Behavioral Characterization." Trends in Neuroscience 13(10):420–423.

Johnston, L. D.; O'Malley, P. M.; and Bachman, J. G. (2000). The Monitoring the Future National Survey Results on Adolescent Drug Use: Overview of Key Findings, 1999 (NIH Publication No. 00–4690). Rockville, MD: National Institute on Drug Abuse.

Kandel, D. B. (1975). "Stages in Adolescent Involvement in Drug Use." Science 73:543–552.

Kandel, D. B., and Yamaguchi, D. B. (1984). "Patterns of Drug Abuse from Adolescence to Early Adulthood:III. Predictor of Progression." American Journal of Public Health 74:673–681.

King, A. J. C.; Boyce, W. F.; and King, M. A. (1999). Trends in the Health of Canadian Youth. Ottawa: Health Canada. Available at http://www.hsc.gc.ca/hppb/childhood-youth/.

Kozel, N. (1997). Epidemiological Trends in Drug Abuse: Advance Report. Washington, DC: National Institute on Drug Abuse. Available at http://www.cdmgroup.com/cewg/doc//697washdc/sum97.advance.html.

National Institute on Drug Abuse (1992). National Household Survey on Drug Abuse: Population Estimates 1992. Rockville, MD: National Institute on Drug Abuse.

—— (1999). National Household Survey on Drug Abuse, National Estimates of Substance Use, 1999. Bethesda, MD: Substance Abuse and Mental Health Services, National Institute on Drug Abuse. Available at http://www.samhsa.gov/OAS/NHSDA/1999/.

World Health Organization (1997). Cannabis: A Health Perspective and a Research Agenda. Geneva: WHO, Division of Mental Health and Prevention of Substance Abuse.

marijuana or marihuana, drug obtained from the flowering tops, stems, and leaves of the hemp plant, Cannabis sativa (see hemp ) or C. indica; the latter species can withstand colder climates. It is one of the most commonly used drugs in the world, following only caffeine , nicotine , and alcoholic beverages in popularity. In the United States, where it is usually smoked, it also has been called weed, grass, pot, or reefer.

The Plant

C. sativa grows as a common weed in many parts of the world, and drug preparations vary widely in potency according to climate, cultivation, and method of preparation. C. indica is a shorter, hardier variety with rounded blue-green leaves, grown in Afghanistan for hashish. Most marijuanas grown in the United States since the late 1980s are hybrids of the two and yield a much more potent product than the marijuana of the past. The resin found on flower clusters and top leaves of the female plant is the most potent drug source and is used to prepare hashish , the highest grade of cannabis. The bud of the female plant, called sinsemilla, is the part most often smoked as marijuana.

The Drug

The effects of marijuana vary with its strength and dosage and with the state of mind of the user. Typically, small doses result in a feeling of well-being. The intoxication lasts two to three hours, but accompanying effects on motor control last much longer. High doses can cause tachycardia, paranoia, and delusions. Although it produces some of the same effects as hallucinogens like LSD and mescaline (heightened sensitivity to colors, shapes, music, and other stimuli and distortion of the sense of time), marijuana differs chemically and pharmacologically.

The primary active component of marijuana is delta-9-tetrahydrocannabinol (THC), although other cannabinol derivatives are also thought to be intoxicating. In 1988 scientists discovered receptors that bind THC on the membranes of nerve cells. They reasoned that the body must make its own THC-like substance. The substance, named anandamide, was isolated from pig brains in 1992 by an American pharmacologist, William A. Devane.

Marijuana lowers testosterone levels and sperm counts in men and raises testosterone levels in women. In pregnant women it affects the fetus and results in developmental difficulties in the child. There is evidence that marijuana affects normal maturation of preadolescent and adolescent users and that it affects short-term memory and comprehension. Heavy smokers often sustain lung damage from the smoke and contaminants. Regular use can result in dependence.

The Legalization Question

With the increase in the number of middle-class users in the 1960s and 1970s, there came a somewhat greater acceptance of the view that marijuana should not be considered in the same class as narcotics and that U.S. marijuana laws should be relaxed. The Drug Abuse Prevention Act of 1970 eased federal penalties somewhat, and 11 states decriminalized possession. However, in the late 1980s most states rewrote their drug laws and imposed stricter penalties. Opponents of easing marijuana laws have asserted that it is an intoxicant less controllable than alcohol, that our drug-using society does not need another widely used intoxicant, and that the United States should not act to weaken UN policies, which are opposed to the use of marijuana for other than possible medical purposes.

Medical Uses

Controversy surrounds the medical use of marijuana, with proponents saying it is useful for treating pain and the nausea and vomiting that are side effects of cancer chemotherapy and for restoring the appetite in people with AIDS. Although its active ingredient, THC (synthesized in 1966 and approved by the U.S. Food and Drug Administration in 1985) is available by prescription in pill form, proponents say it is not as effective as the herb and is more expensive. A 1999 U.S.-government-sponsored study by the Institute of Medicine found that marijuana appeared beneficial for certain medical conditions, such as nausea caused by chemotherapy and wasting caused by AIDS. Because of the toxicity of marijuana smoke, however, it was hoped that further research might lead to development of new delivery systems, such as bronchial inhalers.

The Office of National Drug Control Policy has opposed legalization of the medical use of marijuana, citing law enforcement issues and the possibility that some would use it as a pretext to sell marijuana for nonmedical use, and the FDA said in 2006 that, despite the 1999 report, that marijuana "has no accepted or proven use in the United States." Proponents, disregarding the law, have set up networks for the distribution of the drug to people who they judge will be helped by it and continue to lobby for its legalization for medical use. Voters in several U.S. states have approved initiatives intended to legalize marijuana for medical uses, but, as a result of a Supreme Court ruling in 2005, such initiatives do not protect medical users with a prescription from federal prosecution. Another, lower court ruling permits doctors to discuss medical use of marijuana with their patients but forbids them to help patients obtain the drug. A number of countries, including Canada, permit the medicinal use of the drug.

History of Marijuana Use

Marijuana has been used as an agent for achieving euphoria since ancient times; it was described in a Chinese medical compendium traditionally considered to date from 2737 BC Its use spread from China to India and then to N Africa and reached Europe at least as early as AD 500. A major crop in colonial North America, marijuana (hemp) was grown as a source of fiber. It was extensively cultivated during World War II, when Asian sources of hemp were cut off.

Marijuana was listed in the United States Pharmacopeia from 1850 until 1942 and was prescribed for various conditions including labor pains, nausea, and rheumatism. Its use as an intoxicant was also commonplace from the 1850s to the 1930s. A campaign conducted in the 1930s by the U.S. Federal Bureau of Narcotics (now the Bureau of Narcotics and Dangerous Drugs) sought to portray marijuana as a powerful, addicting substance that would lead users into narcotics addiction. It is still considered a "gateway" drug by some authorities. In the 1950s it was an accessory of the beat generation ; in the 1960s it was used by college students and "hippies" and became a symbol of rebellion against authority.

The Controlled Substances Act of 1970 classified marijuana along with heroin and LSD as a Schedule I drug, i.e., having the relatively highest abuse potential and no accepted medical use. Most marijuana at that time came from Mexico, but in 1975 the Mexican government agreed to eradicate the crop by spraying it with the herbicide paraquat, raising fears of toxic side effects. Colombia then became the main supplier. The "zero tolerance" climate of the Reagan and Bush administrations (1981-93) resulted in passage of strict laws and mandatory sentences for possession of marijuana and in heightened vigilance against smuggling at the southern borders. The "war on drugs" thus brought with it a shift from reliance on imported supplies to domestic cultivation (particularly in Hawaii and California). Beginning in 1982 the Drug Enforcement Administration turned increased attention to marijuana farms in the United States, and there was a shift to the indoor growing of plants specially developed for small size and high yield. After over a decade of decreasing use, marijuana smoking began an upward trend once more in the early 1990s, especially among teenagers, but by the end of the decade this upswing had leveled off well below former peaks of use.

Bibliography

See J. S. Hochman, Marijuana and Social Evolution (1972); E. Marshal, Legalization (1988); M. S. Gold, Marijuana (1989); L. Grinspoon and B. J. Bakalar, Marijuana: The Forbidden Medicine (1995); publications of the Drugs & Crime Data Center and Clearinghouse, the Bureau of Justice Statistics Clearinghouse, and the National Clearinghouse for Alcohol and Drug Information.

Marijuana

Definition

Marijuana and its medically active components, called cannabinoids, are used in cancer therapy to reduce nausea and vomiting caused by chemotherapeutic medications. This drug, however, is considered an illegal substance in the United States.

Purpose

Marijuana can be used with a variety of cancer chemotherapeutic agents that cause nausea and vomiting. Marijuana seems to work best at preventing nausea and vomiting with mild to moderately active chemotherapeutic agents. There are limited studies showing it does help reduce nausea and vomiting caused by the most powerful cancer chemotheraupeutic drugs. Marijuana may also be used by cancer patients to stimulate appetite.

Description

Marijuana, a plant with known psychoactive properties, has been used by human beings for thousands of years as a medicine. Ancient Chinese writings tell of its use for headaches, menstrual pains, and abdominal distress. It was used in the United States as a medicine for a variety of aliments until 1937, when its use was discouraged by the Marijuana Tax Act, which imposed high taxes on its use. In 1970, it was classified by the U.S. Government as a drug having no known medical use and a high potential for abuse. However, people who use marijuana recreationally have long reported that the drug helped ease nausea and vomiting, leading to its use by cancer patients to help ease the nausea and vomiting brought about by many anti-cancer medications. Because of its illegal status, there are very few well-researched studies examining the effectiveness of marijuana.

When the drug is smoked, it is immediately absorbed into the bloodstream through the rich network of blood vessels in the lungs. Within five to ten minutes the most active chemical part of marijuana, delta-9-THC, reaches the brain, where it produces its anti-nausea and anti-vomiting effects. These effects peak in about one hour, and last for about three hours.

Recommended dosage

Since marijuana is still an illegal drug under federal law, there are no uniform recommended dosages. The amount of delta-9-THC in marijuana determines the strength of the drug, which in turn will affect the amount needed for therapeutic effects.

When marijuana is smoked, the patient can alter the dosage of delta-9-THC simply by altering how much smoke is inhaled, the amount of time taken between inhalations, how deeply the smoke is inhaled, and how long the smoke is held in the lungs. Since the anti-nausea and anti-vomiting effects of marijuana are so rapid in onset, most patients quickly learn how much marijuana they need to smoke to achieve the desired results.

Marijuana can also be taken orally, most commonly either in a tea or baked in cookies. When used this way, the dosage a patient receives is more variable than smoking due to a slower absorption rate in the stomach versus the lungs. A pill containing THC known as dronabinol, is taken as an initial dose of five mg one to two hours before chemotherapy treatment. It can be then taken as five mg every two to four hours after treatment for up to six times a day.

Precautions

The few studies that have examined the safety of marijuana all seem to agree that it is a relatively safe drug. The chances of an overdose appear quite small. However, high doses can lead to tachycardia, or rapid heart rate, in a small percentage of users. Because of this, people with a history of heart problems should only use marijuana under the supervision of a trained health care provider. Since marijuana is also known to cause drowsiness, it should not be used in situations in which people need to remain alert, such as driving. In addition, smoking marijuana increases the risk of lung cancer.

Side effects

The side effects of marijuana use may or may not occur, depending on such variables as the dosage used, the method used to take the drug, and the frame of mind of the patient when using the drug. Typical side effects include euphoria, which is a feeling of well being, along with talkativeness and spontaneous laughter. These side effects are usually seen within a half hour of inhaling or ingesting the drug.

Drowsiness, or feeling sleepy, is another common side effect of using marijuana. The drowsiness appears to be dose related. Other side effects commonly seen are "red eye." This effect is caused by the dilation, or widening of the blood vessels in the eye. A rapid heart rate, or tachycardia, is seen in marijuana users. This side effect also appears to be dose related, and usually occurs within 20 minutes of drug use and stops after about 45 minutes. Marijuana users also usually experience an increased appetite. It generally occurs within one hour of using the drug.

Rarely, more troublesome side effects can be seen after marijuana use. These side effects more often occur in people using large does of the drug, or smoking marijuana that is particularly potent. Side effects seen in these instances can include depression , anxiety, paranoia, confusion, and hallucinations. These side effects generally last only as long as one is using the drug, and do not generally reappear unless marijuana is used again.

Interactions

Marijuana appears to alter the absorption and elimination of certain other drugs, although studies are limited on this subject. Due to its tendency to make people sleepy or tired, marijuana should not be used with alcohol, sedatives, or sleeping pills. It has also been reported that marijuana increases the elimination of theophylline, which is a medication used in the treatment of asthma.

Resources

BOOKS

Grinspoon, Lester and James B. Balalar. Marijuana, the Forbid den Medicine. New Haven:Yale University Press, 1997.

Joy, E. Janet, Stanley J. Watson Jr., and John A. Benson Jr. ed. Marijuana and Medicine. Washington D.C.: National Academy Press, 1999.

Mathre, L. Mary, ed. Cannabis in Medical Practice. Jefferson, N.C.:McFarland & Company, 1997.

OTHER

Women's Alliance for Medical Marijuana. <http://www.wamm.org>.

Canadian Medical Marijuana Association. <http://communities.msn.ca/CanadianMedicialMarijuanaAssociation>.

Edward R. Rosick, DO, MPH, MS

Marijuana

Marijuana is the common name for the drug obtained from the hemp plant, Cannabis sativa. Hemp is a tall annual plant that can grow in almost any climate. Native to central and western Asia, hemp is one of the oldest crops cultivated by humans. Hemp's most common agricultural use has been as a source of linen, rope, canvas, and paper.

Hemp contains more than 400 chemicals. The main psychoactive (affecting the mind or behavior) chemical is tetrahydrocannabinol, commonly referred to as THC. For over 3,000 years, the dried ground leaves, flowers, and stems of the plant have been smoked, eaten, chewed, or brewed as a medicine to relieve symptoms of illness. From the seventeenth to the early twentieth century, marijuana was considered a household drug useful for treating such maladies as headaches, menstrual cramps, and toothaches.

In the 1920s, as a result of the Eighteenth Amendment to the U.S. Constitution forbidding the manufacture and sale of alcoholic beverages (Prohibition), the use of marijuana as a psychoactive drug began to grow. Even after the repeal of Prohibition in 1933, marijuana (along with morphine, heroin, and cocaine) continued to be widely used. In 1937, 46 states banned the use of marijuana.

In 1985, the Food and Drug Administration (FDA) gave approval for the use of two psychoactive chemicals from marijuana to prevent nausea and vomiting after chemotherapy in cancer treatment. Medical researchers also propose using marijuana to ease the effects of glaucoma (a serious vision disorder), as a bronchodilator (a drug that helps open the bronchial air passages in the lungs), and as an antidepressant.

The origin of the word marijuana is not known, but it appears to be a combination of the Spanish names Maria and Juana (Mary and Jane). The drug slang for marijuana includes such names as Mary Jane, pot, grass, herb, tea, reefer, and weed. Hashish is the highest grade of marijuana. It is made from the resin found on flower clusters and top leaves of the female hemp plant.

Words to Know

Cannabis sativa : The botanical name for the hemp (marijuana) plant.

Dopamine: Brain chemical responsible for causing feelings of reward.

Glaucoma: An eye disease that seems to be helped by the main psychoactive compound in marijuana.

Hashish: A more potent form of marijuana that comes from the flower clusters and top leaves of the female hemp plant.

Prohibition: Eighteenth Amendment to the U.S. Constitution that prohibited the use and sale of alcohol.

Psychoactive drugs: Drugs that contain chemicals that effect the mind or behavior.

Tetrahydrocannabinol (THC): The main psychoactive compound in marijuana.

Effects

The effects of marijuana on a user change dramatically as the dosage increases. Taken at low doses, marijuana tends to make a user drowsy and relaxed. The user may also feel a general sense of well-being. As the dose increases, a user may experience an altered sense of time and awareness, and may have difficulty completing thoughts and taking part in conversation. A user's sense of balance and short-term memory (remembering very recent events or from one moment to the next) may also be affected. At higher doses, severe psychological disturbances can take place, such as paranoia, hallucinations, and panic attacks.

Marijuana affects the cardiovascular system by increasing heart rate and dilating (expanding) blood vessels in the eyes. Difficulty in coordinating body movements and pains in the chest may be other effects of the drug. Scientists believe that long-term use of marijuana damages the lungs in a manner similar to tobacco smoking.

Scientific studies released in mid-1997 indicate that people who smoke large amounts of marijuana may experience changes in their brain chemistry. These changes are similar to those seen in the brains of people who abuse addictive drugs such as heroin, cocaine, nicotine, and alcohol.

All addictive drugs increase the amount of dopamine in the brain. Dopamine is a brain chemical responsible for causing feelings of reward. The new studies found (for the first time) that high doses of marijuana increased the levels of dopamine in the brain. Constant use of addictive drugs, however, can cause the brain to lose its ability to produce high levels of dopamine. When this happens, a drug user feels a greater need for the drug, or for even stronger drugs. Scientists believe this may occur with marijuana.

Users of addictive drugs feel withdrawal symptoms (feeling anxious, edgy, and unable to cope) when they stop taking the drugs. It was previously believed that marijuana users did not suffer feelings of withdrawal. However, the recent studies indicate that heavy users of marijuana smoke not so much for the "high" but to calm their feelings of anxiety brought on by withdrawal from the drug. Since THC is absorbed primarily in the fat tissues and lingers in the bloodstream, withdrawal symptoms are not as evident as with fast-acting drugs like nicotine.

Possible medical benefits

In 1985, the FDA gave approval for the use of two psychoactive chemicals from marijuana to help prevent the nausea and vomiting many cancer patients experience after receiving chemotherapy. For these patients, THC can be prescribed in capsule form.

Research suggests that compounds (other than THC) inhaled when smoking marijuana can also be used for medicinal purposes. Marijuana may help stop the weight loss in AIDS patients, it may lower eye pressure in people with glaucoma, it may control spasms in multiple sclerosis patients, and it may help relieve chronic pain. Currently, thirteen states have legalized marijuana for medicinal purposes. None of these states, however, actually distribute the medicinal marijuana because it is still illegal to buy the drug from the federal government.

In mid-1999, the National Institutes of Health (NIH) issued a policy that stated the need for further research into the possible use of marijuana for medical treatment. In May 2001, the U.S. Supreme Court ruled that medical use of marijuana violates federal law and that there could be no exception.

[See also Addiction ]

Marijuana

The common name of a small number of varieties of Cannabis sativa, or Indian hemp plant, which contain tetrahydrocannabinol (THC), a psychoactive drug.

Cannabis, in the form of marijuana, hashish (a dried resinous material that seeps from cannabis leaves and is more potent than marijuana), or other cannabinoids, is probably the most often used illegal substance in the world. In the United States, marijuana use became widespread among young people in the 1960s. By 1979, 68 percent of young adults between the ages of 18 and 25 had experimented with it at least once, and it was reported that as of the same year the total number of people in the U.S. who had tried the drug was 50 million. In the late 1980s, it was estimated that about 50 to 60 percent of people between the ages of 21 and 29 had tried marijuana at least once.

Marijuana and hashish are usually smoked, but may also be ingested orally, and are sometimes added to food or beverages. The psychoactive substance of cannabis is tetrahydrocannabinol, or THC, especially delta-9-tetrahydrocannabinol. Delta-9-THC can be synthesized, is known to affect the central nervous system , and has been legally used to treat side-effects of chemotherapy and weight loss in persons affected with AIDS. Other legal therapeutic uses of marijuana include the treatment of glaucoma and epilepsy .

The effects of cannabis use vary from individual to individual, depending on the physical and psychological condition of the user, the amount of THC consumed, and

many other factors. Technically, marijuana is classified as a hallucinogen, but its effects are usually much milder than those of other drugs in this category, such as LSD, mescaline, and psilocybin. When it is inhaled through a marijuana cigarette, THC reaches its highest concentration in the blood within a half hour, and is absorbed by the brain and other organs, and can affect consciousness for several hours. THC can remain stored in body fat for several weeks. Marijuana users commonly experience feelings of euphoria, self-confidence, reduced inhibition, relaxation, and a floating sensation. Feelings of giddiness and mild feelings of paranoia are also common. Physiological effects include increases in pulse and heart rates, reddened eyes, dryness of the mouth, and an increased appetite. The initial euphoric feelings after ingesting marijuana are generally followed by sleepiness. Although marijuana has been known to produce psychological dependence, there is little tendency to become physically dependent on it, and withdrawal from the drug does not pose medical problems. Recently, receptors for THC have been discovered in the brain, together with a naturally-occurring substance—anandamide—that binds the chemical to its receptors and may be a neurotransmitter .

Documented negative effects of marijuana use include impairment in perception , sensory motor coordination, short-term memory , and panic attacks, and is also linked to impairment of the immune system, lowered testosterone levels in males, and chromosome damage. If taken by pregnant women, marijuana affects the developing fetus. Long-term marijuana smokers display similar respiratory dysfunctions as tobacco smokers In research on rats, THC has been found to destroy cells in the hippocampus, a part of the brain that is important in the formation of new memories. Psychologically, chronic use of marijuana has been associated with a loss of ambition known as amotivational syndrome. Authorities differ with respect to the physical and psychological risks of short-term and long-term use/abuse of cannabis. Current penalties for the illegal possession of marijuana, hashish, or other form of cannabis can be extremely severe.

See also Drugs/Drug abuse

Further Reading

Grinspoon, Lester. Marijuana Reconsidered. Oakland, CA: Quick American Archives, 1994.

MARIJUANA

MARIJUANA, also spelled "marihuana," whose scientific name is cannabis sativa, is a drug obtained from the stems and leaves of the Indian hemp plant. Marijuana is one of the most commonly used drugs in the world: a 1999 survey on drug abuse showed that 75 percent of illicit drug dealers smoked it. It has several intrinsic virtues: it is an analgesic, an anesthetic, an antibiotic, an anti-depressant, and a sedative, depending on its dosage.

Marijuana was introduced into India from China and from there it spread to North Africa and Europe as early as a.d. 500. The Spanish introduced it to the New World in 1545. The English settlers at Jamestown (1611) used hemp produced from the marijuana plant's fibers to make clothes. The hemp industry started in Kentucky in 1775 (in 1860, 40,000 tons were produced). The Harrison Narcotics Act became law in 1914 and aimed at controlling the sale of narcotics. Utah became the first state to pass an anti-marijuana law in 1915, and by 1931 twenty-nine states had criminalized the non-medical use of marijuana. Congress then passed the 1937 Marijuana Tax Act which prohibited its non-medical use while requiring the people producing, distributing, and using it for medical reasons to register and to pay a tax. In 1942, marijuana was removed from the American Pharmacopoeia because of its addictive qualities, and side effects such as anxiety, sleeplessness, paranoia, and altered time perception.

Evaluations of marijuana and its effects vary radically. In the 1950s the beatniks praised it (as would the hippies of the 1960s) as a gesture of protest against materialistic society and as a possible means of attaining enlightenment, though this assumption was later declared mistaken by such a counter-cultural figure as Allen Ginsberg. The 1970 Controlled Substances Act classified it as extremely dangerous and harmful. Until the 1970s marijuana came mostly from Mexico. By 1975 Colombian marijuana had inundated the American market. Because of drastic measures adopted under the Reagan and Bush administrations, such as the 1986 Anti-Drug Abuse Act, marijuana consumption and imports dropped sharply. Some Americans, young and old, however, continued to cultivate it at home, mainly in California and Hawaii. In 1992, the National Institute of Drug Abuse estimated that 67 million Americans—about one out of three—had smoked marijuana at least once in their lives. In 1996 California adopted Proposition 215, which allowed seriously ill people to obtain and consume marijuana for medical purposes. Connecticut, Louisiana, New Hampshire, Ohio, Vermont, and Wisconsin adopted such laws in 1998. Hawaii became the first state to decriminalize marijuana in June 2000. On 14 May 2001 the Supreme Court ruled eight to zero against authorizing the medicinal use marijuana under federal law.

BIBLIOGRAPHY

Bonnie, Richard J., Charles H. Whitebread, and Dana L. Farnsworth. The Marijuana Conviction: A History of Marijuana Prohibition in the United States. New York: The Lindesmith Center. 1999.

Mathre, Mary Lynn. Cannabis in Medical Practice: A Legal, Historical, and Pharmacological Overview of the Therapeutic Use of Marijuana. Jefferson, N.C.: McFarland and Company, 1997.

Sloman, Larry R. Reefer Madness: The History of Marijuana inAmerica. Griffin Trade Paperback, 1998.

FrédéricRobert

See alsoDrug Trafficking, Illegal .

marijuana Narcotic drug prepared from the dried leaves of the Indian hemp plant (Cannabis sativa); it is different from hashish, which is prepared from resin obtained from the flowering tops of the plant. Possession of the drug is illegal in many countries. See also addiction

ma·ri·jua·na / ˌmarəˈ(h)wänə/ (also ma·ri·hua·na) • n. cannabis, esp. as smoked in cigarettes.

marijuana (ma-ri-hwah-nă) n. see cannabis.

marijuana, marihuana XIX. — Amer. Sp.

marijuana See CANNABIS.

marijuana •Alana, Anna, bandanna, banner, Branagh, canna, canner, Diana, fanner, Fermanagh, Guyana, Hannah, Havana, hosanna, Indiana, Joanna, lanner, Louisiana, manna, manner, manor, Montana, nana, planner, Pollyanna, Rosanna, savannah, scanner, spanner, Susanna, tanner •Abner • Jaffna • Patna • caravanner •Africana, Afrikaner, Americana, ana, banana, Botswana, bwana, cabana, caragana, Christiana, Dana, darner, Edwardiana, garner, Georgiana, Ghana, Gloriana, Guiana, gymkhana, Haryana, iguana, Lana, lantana, liana, Lipizzaner, Ljubljana, Mahayana, mana, mañana, marijuana, nirvana, Oriana, pacarana, piranha, prana, Purana, Rosh Hashana, Santayana, Setswana, sultana, Tatiana, Tijuana, Tirana, tramontana, Tswana, varna, Victoriana, zenana •Gardner • partner •antenna, Avicenna, duenna, henna, Jenna, Jenner, Morwenna, Ravenna, senna, Siena, sienna, tenner, tenor, Vienna •Edna • interregna • Etna • Pevsner