Aloe

Definition

Aloe is a medicinal plant with a history of use dating back to ancient Egypt. It may be most well known for its effects on easing sun burn. Aloe is a succulent plant from South Africa and is often used as a ornamental plant in the garden.

Description

There are over 200 different species of aloe plants. The type used most often for medicinal purposes is Aloe barbadensis, also known as Aloe vera. Both Aloe barbadensis and Aloe arborescens are grown commercially. As a desert plant it cannot survive frost and is grown in the southern United States.

There are two separate medicinal products obtained from the aloe plant. The most common is the gel obtained from the inner tissue of the thick, fleshy leaves of aloe. The gel has gained acceptance as a base for nutritional drinks, a moisturizer for the skin and a healing agent in cosmetics. It can be found in numerous toiletry products and over-the-counter drugs. This gel can be manually squeezed out of a leaf of aloe and used directly on the skin. The gel is nutrient rich and, thus, has health benefits.

The leaves also produce a liquid juice or resin that is sometimes referred to as aloes, Aloin or aloe latex. This latex is yellowish in color and bitter tasting. It contains anthraquinone glycosides, which are potent laxatives . The aloe latex has a long history of use taken internally as a laxative.

The list of medicinal claims for aloe is extensive. In recent years several companies have made their mark in the aloe market through possibly questionable ethics and multilevel marketing techniques that exaggerated claims. The most well established uses for aloe are topically forminor skin conditions and as amoisturizer. For this reason, aloe is often found in cosmetics products.

Some of the claims and suggested uses for aloe include:

• oral use of Aloe vera to control blood sugar levels in people with type II diabetes
• oral use of aloe in cancer prevention has been investigated
• use as a laxative
• using aloe gel to treat minor wounds and inflammatory disorders of the skin as well as burns
• topical use to treat genital herpes
• topical use in a cream, for treatment of psoriasis
• topical use in a lotion for treating dandruff
• topical use as a treatment for radiation induced skin damage
• use as an immune stimulant
• uses for its antibacterial and antifungal activity
• oral use to relieve symptoms of stomach ulcer
• use in treating ulcers of the mouth or canker sores

Scientific data is weak on most of these claims. Research does support the use of aloe vera on first to second degree burns as well as for bed sores. There is a limited amount of data indicating that aloe may be useful to relieve inflammation due to inflammatory bowel disease when taken orally. Aloe latex is effective as a laxative but there may be safer laxatives to take when necessary.

Recommended dosage

No recommended dosage has been established for aloe or products containing aloe. Since the U.S. Food and Drug Administration (FDA) does not regulate herbs and supplements, the effective doses are often recommended by the manufacturer. In cosmetics, aloe gel is often used at 0.5%. It is generally accepted that aloe gel can be used liberally on the skin. The gel can be taken orally from 50-200 mg daily. For use as a laxative, the dried juice can be taken in capsule form from 40-200 mg daily. Establishing a recommended dose is difficult because the concentration of active ingredients varies from product to product. Product labels should be read for recommended dosages. Injection of aloe products is not recommended.

Precautions

Some species of aloe are toxic and should not be used. People who grow their own aloe should be sure the species is safe for medicinal use. The most common aloe that is used medicinally is Aloe barbadensis. The FDA does not strictly regulate herbs and supplements so strength, purity and product safety may vary. It is important to know if purchased aloe is in the gel or latex form. The only use aloe latex is as a laxative. There is the potential that the latex fraction of aloe can cause uterine contractions so this drug should not be used during pregnancy. The gel form is safe in most instances. There have been reports of injected aloe causing death.

Side effects

Aloe may cause allergic reactions or sensitivities in some people. Anyone with a known allergy to members of the Liliaceae family such as garlic , onions

QUESTIONS TO ASK YOUR PHARMACIST

• Is the aloe product I selected from the gel or the latex? (The latex is used as a laxative, while the gel is used for nutritional value and skin care.)
• How can I determine the proper dosage for my condition?
• Are there side effects I should be aware of?

or tulips should avoid aloe. If irritation occurs when using a product containing aloe its use should be stopped immediately. Oral consumption of aloe latex can cause abdominal pains, gastro-intestinal irritation and, in large amounts, can lead to kidney problems, bloody diarrhea and bleeding in the intestines. Aloe should not be used as a laxative for more than 1–2 weeks without medical supervision. When used on surgical wounds aloe gel has been found to slow the healing of the lesion.

Interactions

There are no known drug interactions with aloe.

Caregiver concerns

Caregivers should be aware of a patients use of aloe for medicinal purposes. They should review the recommended uses and dosages on the package label and monitor how and when the patient uses aloe for treatment. It is important that the caregiver recognize any allergic reactions or harmful side effects the patient experiences, especially from use as a laxative.

Resources

BOOKS

Evans, W. C. Trease and Evans Pharmacognosy. London: W. B. Saunders, 2002.

PERIODICALS

Langmead, L., et al. “Randomized, Double-blind, Placebo-controlled Trial of Oral Aloe Vera Gel for Active Ulcerative Colitis.” Aliment Pharmacology & Therapeutics 19, no. 7 (April 1, 2004): 739–47.

Maenthaisong, R., N. Chaiyakunapruk, S. Niruntraporn, and C. Kongkaew. “The Efficacy of Aloe vera Used for Burn Wound Healing: A Systematic Review.” Burns 33, no. 6 (September 2007): 713–8.

Moore, Z. E., and S. Cowman. “Wound Cleansing for Pressure Ulcers.” Cochrane Database Systematic Reviews 4 (October 19, 2005): CD004983.

OTHER

“Definition, Testing and Application of Aloe Vera and Aloe Vera Gel.” Nature4Science. http://www.nature4science.com/AloeVera/1_DescriptionofAloeVera.pdf.

Natural Standard Research Collaboration. “Aloe (Aloe vera).” MayoClinic.com. May 1, 2006 [cited April 9, 2008]. http://www.mayoclinic.com/health/aloevera/NS_patient-Aloe.

Cindy L.A. Jones Ph.D.