Desipramine

Definition

Desipramine is an antidepressant drug used to elevate mood and promote recovery of a normal range of emotions in patients with depressive disorders. In addition, desipramine has uses in a number of other psychiatric and medical conditions. In the United States, the drug is also known by its brand name, Norpramin.

Purpose

Desipramine is known principally as an antidepressant drug used to promote recovery of depressed patients. It also has therapeutic uses in panic disorder , pain management, attention-deficit/hyperactivity disorder (ADHD), sleep attacks ( narcolepsy and cataplexy), binge eating (bulimia), and in cocaine craving in the treatment of addiction .

Description

Desipramine is one of the tricyclic antidepressants, so-called because of the three-ring chemical structure common to these drugs. Until the late 1980s, desipramine and other tricyclic antidepressants, such as imipramine , formed the mainstay of the pharmacological treatment of depressive disorders.

The therapeutic action of antidepressants is not completely understood. It is known that these drugs boost the levels of certain messenger chemicals, called neurotransmitters , which are involved in transmitting signals between nerve cells in the brain . This action may help to restore normal emotional feelings by counteracting abnormalities of nerve signal transmission that occur in depressive disorders.

Desipramine is one of a large number of tricyclic antidepressant compounds. Each was developed for somewhat differing pharmacological effects and side-effect profiles. The effects of desipramine are very similar to those of other tricyclics, although some individual patients may find one drug of this group more effective or more tolerable than another. It is available as Norpramin in 10-, 25-, 50-, 75-, 100-, and 150-mg tablets, although generic manufacturers may supply a somewhat different set of dosages.

Recommended dosage

For adults, desipramine is usually administered in dosages of 100–200 mg per day. Doses ranging from 75 mg to 300 mg per day are sometimes prescribed. The initial daily dose is usually low to avoid side effects, and it is usually increased, as necessary, until a therapeutic effect is achieved. Desipramine may be administered in divided doses or a single daily dose.

Geriatric patients, children, and adolescents are more sensitive to the side effects and toxicities of tricyclic antidepressants than other people. For geriatric patients, the dose may range from 25 to 100 mg per day. For children six to 12 years old, the recommended dose ranges from 10 to 30 mg per day in divided doses. For adolescents, daily dosages range from 25 to 50 mg but may be increased up to 100 mg, if needed.

Precautions

Desipramine and other tricyclic antidepressants may cause drowsiness. Activities requiring alertness, such as driving, may be impaired. Dizziness or lightheadedness may occur on arising due to sudden decreases in blood pressure. Fainting may occur. Some patients may experience difficulty urinating, especially men with prostate enlargement. Glaucoma may be aggravated. Sensitivity to ultraviolet light may be increased, and sunburns may occur more easily. Sweating may be reduced, causing sensitivity to heat and hot weather. Among patients with epilepsy, seizures may become more frequent.

Tricyclic antidepressants, including desipramine, should be used with caution in patients with heart disease because of the possibility of adverse effects on heart rhythm. Adverse effects on the heart occur frequently when tricyclics are taken in overdose. Only small quantities of these drugs should be given to patients who may be suicidal.

Tricyclic antidepressants may cause dry mouth due to decreased saliva, possibly contributing to the development of tooth decay, gum disease, and mouth infections. Patients should avoid sweets, sugary beverages, and chewing gum containing sugar.

It has not been determined whether desipramine is safe to take during pregnancy, and the patient's need for this medicine should be balanced against the possibility of harm to the fetus. Tricyclic antidepressants may be secreted in breast milk and may cause sedation and depressed breathing in a nursing infant.

Side effects

Desipramine may cause many side effects. Initially, the side effects of tricyclic drugs may be more pronounced, but sensitivity may decrease with continued treatment. The following more common side effects are grouped by the body system affected:

Cardiovascular: decreases of blood pressure on rising from a sitting or lying position, which may cause dizziness or fainting; increases of blood pressure, rapid heart rate, pounding heart, altered heart rhythm.
Nervous system: sedation, confusion, nervousness, restlessness, sleep difficulties, numbness, tingling sensations, tremors, increased seizure tendency.
Autonomic: blurred vision, dry mouth, decreased sweating, difficulty urinating, constipation.
Skin: rashes, sensitivity to sunlight.
Body as a whole: weight gain.

Less commonly, tricyclic drugs may cause adverse effects on almost any organ or system of the body, particularly the blood, hormones, kidney, and liver. Patients should consult their physicians if symptoms develop or bodily changes occur.

Interactions

Tricyclic antidepressants, such as desipramine, may interact with many other drugs. Patients should inform their physicians about all other drugs they are taking. Tricyclic drugs may intensify the effects of drugs causing sedation, including alcohol, barbiturates , narcotic pain medications, minor tranquilizers, and antihistamines. Tricyclics may cause excessive reductions of blood pressure in patients taking blood pressure medicine, especially on arising or standing up. Conversely, these drugs may interfere with the pressure-reducing effects of certain other blood pressure medicines. Tricyclics may interact with thyroid medications to produce heart rhythm abnormalities. Also, they may increase seizure tendency in patients with epilepsy, requiring adjustment of anti-epileptic medication. Concurrent use of tricyclic antidepressants with other antidepressants or other psychiatric medicines may result in intensification of certain side effects.

Certain drugs may interfere with the elimination of tricyclic antidepressants from the body causing higher blood levels and increased side effects. This effect may occur with cimetidine (Tagamet), other antidepressants, methylphenidate (Ritalin, Concerta), and some antipsychotic medications.

Resources

BOOKS

American Society of Health-System Pharmacists, Inc. AHFS Drug Information, edited by Gerald K. McEvoy, Pharm.D. Bethesda, MD: American Society of Health-System Pharmacists, Inc., 2001.

Hardman, Joel G., Alfred Goodman Gilman, Lee E. Limbird. Goodman and Gilman's The Pharmacological Basis of Therapeutics. 9th ed. New York: McGraw-Hill, 1996.

Medical Economics Co. Staff. Physicians' Desk Reference. 55th ed. Montvale, NJ: Medical Economics Company, Inc., 2001.

Nissen, David, ed. Mosby's GenRx. 11th ed. St. Louis: Mosby, Inc., 2001.

The United States Pharmacopeial Convention, Inc. USP DI(r) Volume I–. Drug Information for the Health Care Professional. 21st ed. Englewood, CO: Micromedex, Inc., 2001.

The United States Pharmacopeial Convention, Inc. USP DI(r) Volume II–. Advice for the Patient. 21st ed. Englewood, CO: Micromedex, Inc., 2001.

Richard Kapit, M.D.