Alprazolam

Alprazolam

Definition

Alprazolam is a tranquilizer. It belongs to a group of drugs called benzodiazepines. In the United States alprazolam is sold under brand name Xanax.

Purpose

The United States Food and Drug Administration has approved alprazolam to treat anxiety, panic disorder , and anxiety associated with depression. Occasionally alprazolam is used to treat alcohol withdrawal, but it is not FDA-approved for this use, and is not normally the first drug tried in treating alcohol withdrawal symptoms.

Description

Alprazolam is classified as a benzodiazepine. Benzodiazepines are sedative-hypnotic drugs that help to relieve nervousness, tension, and other anxiety symptoms by slowing the central nervous system. To do this, they block the effects of a specific chemical involved in the transmission of nerve impulses in the brain , decreasing the excitement level of the nerve cells.

All benzodiazepines cause sedation, including drowsiness and reduced mental alertness. However, one benefit of alprazolam is that it causes somewhat less drowsiness than many other benzodiazepine drugs.

Alprazolam comes in 0.25-mg, 0.5-mg, 1-mg and 2-mg tablets, and 1-mg/ml solution.

Recommended dosage

The recommended initial adult dose for anxiety is 0.25–0.5 milligrams (mg) taken three times daily. This dosage may be increased every three to four days to a maximum total of 4 mg daily. Dosage for alcohol withdrawal usually totals from 2–2.5 mg daily given in several small doses throughout the day.

The starting dose for treating panic disorder is 0.5 mg three times daily. This dosage may be increased every three to four days until the total daily dosage ranges from 2–10 mg. The total amount should be divided in at least three even daily doses. Average doses for anxiety associated with depression range from 2.5–3 mg daily divided into even doses.

Precautions

Alprazolam should not be used by patients who are pregnant, have narrow angle glaucoma, take ketoconazole or itraconazole, or those who are allergic to this or any other benzodiazepine drug. The dose of alprazolam must be carefully regulated and individualized in the elderly (over age 60), people with liver or kidney disease, and those taking other medications used to treat mental disorders.

Because alprazolam is a nervous system and respiratory depressant, it should not be taken with other similar depressants, such as alcohol, other sedatives, sleeping pills, or tranquilizers. People taking this drug should not drive, operate dangerous machinery, or engage in hazardous activities that require mental alertness at least until they see how the drug affects them.

Alprazolam should be used under close physician supervision in patients with history of substance abuse. Like other benzodiazepines, alprazolam can be habit-forming. Risk and severity of dependence appears greater in patients taking doses larger than 4 mg daily. However, smaller doses may cause dependence if alprazolam is taken longer than 12 weeks.

Suddenly discontinuing alprazolam after several weeks may cause uncomfortable symptoms of withdrawal. Withdrawal symptoms in people who have taken alprazolam three months or longer may include seizures , anxiety, nervousness, and headache. Patients should discuss with their doctor how to gradually discontinue alprazolam use to avoid such symptoms.

Side effects

The most common side effects of alprazolam include sedation, dizziness, drowsiness, insomnia , and nervousness. The intensity of these side effects usually declines gradually and subsides in about eight weeks. A drop in blood pressure and an increase in heart rate may also occur in people who are taking alprazolam.

Decreased sex drive, menstrual disorders, and both weight gain and weight loss has been associated with alprazolam use. People who experience the side effects of stomach upset, nausea, vomiting, and dry mouth should eat frequent, small meals and/or chew sugarless gum. Alprazolam has been associated with both diarrhea and constipation, as well as tremor, muscle cramps, vision disturbances, and rash.

Interactions

Alprazolam interacts with a long list of other medications. Anyone starting this drug should review the other medications they are taking with their physician and pharmacist for possible interactions. The most severe interactions occur with antifungal medications, such as ketoconazole, itraconazole, and fluconazole. These are associated with alprazolam toxicity (excessive sedation, fatigue , slurred speech, slowed reactions and other types of psychomotor impairment).

Estrogens (female hormones), erythromycin (an antibiotic), fluoxetine (Prozac, Sarafem), cimetidine (Tagamet), isoniazid, and disulfiram (Antabuse) can increase the effects of alprazolam. Carbamazepine can make alprazolam less effective. When alprazolam is combined with other sedative drugs (tranquilizers, sleeping pills) or alcohol, its depressants effects are more intense. These combinations should be avoided.

Resources

BOOKS

Kay, Jerald. Psychiatry: Behavioral Science and Clinical Essentials. Philadelphia: W. B. Saunders Company, 2000.

Lacy, Charles F. Drug Information Handbook. Hudson, OH: Lexi-Comp, Inc. 2002.

Pharmacia and Upjohn Company Staff. Product Information: Xanax, alprazolam. Kalamazoo, MI: Pharmacia and Upjohn Company, 1999.

Ajna Hamidovic, Pharm.D.