For the Consumer

Applies to reserpine: oral tablet

What are some side effects that I need to call my doctor about right away?

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

• Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
• Signs of low mood (depression), thoughts of killing yourself, nervousness, emotional ups and downs, thinking that is not normal, anxiety, or lack of interest in life.
• Chest pain or pressure.
• Enlarged breasts.
• Breast soreness.
• Not able to sleep.
• Not able to get or keep an erection.
• Lowered interest in sex.
• Very bad dizziness or passing out.
• Hearing loss.
• Change in eyesight.
• Not hungry.
• Bad dreams.
• Slow heartbeat.
• A heartbeat that does not feel normal.
• Swelling.
• Shortness of breath.
• Trouble controlling body movements.
• Very nervous and excitable.
• Pain when passing urine.

What are some other side effects of this drug?

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

• Dizziness.
• Feeling sleepy.
• Dry mouth.
• Headache.
• Muscle pain.
• Stuffy nose.
• Upset stomach or throwing up.
• Diarrhea.
• Anxiety.
• Weight gain.
• Nosebleed.

These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.

You may report side effects to the FDA at 1-800-FDA-1088. You may also report side effects at http://www.fda.gov/medwatch.

For Healthcare Professionals

Applies to reserpine: oral tablet

General

In one study of 231 hospitalized patients, 26 (11.3%) reported adverse side effects. Of these 26 patients, three (1.2%) patients developed side effects that were considered life-threatening. Adverse reactions were observed within the first two days of therapy in 62% of patients who experienced side effects.

Respiratory

The most common side effect is nasal congestion, reported in 8% of patients. A rare respiratory system side effect is bronchospasm.

Rare reports of reserpine-induced bronchospasm are believed to be due to inactivation of beta-adrenergic receptors, which can result in a marked potentiation of the bronchoconstrictive effect of histamine.

Nervous system

Increased parkinsonian movements upon reserpine withdrawal (as with neuroleptics) may be due to supersensitivity to dopamine as a result of increased dopamine receptors that developed during reserpine therapy.

Common nervous system side effects include sedation, lethargy (different from the psychiatric syndrome of depression), drowsiness, weakness, vertigo, insomnia, or headache in approximately 1% to 5% of patients. While reserpine is used to treat tardive dyskinesia, extrapyramidal movements may worsen upon withdrawal of therapy. A case of CNS hypertension, believed to be due to cerebral edema, has been associated with the use of reserpine.

Psychiatric

Psychiatric problems related to reserpine therapy can be serious. Depression occurs in 2% to 28% of patients, is more likely when daily doses exceed 0.5 mg, and can present at any time during therapy. Suicidal ideation has been reported. Reserpine-induced depression is quickly reversible if therapy is withdrawn as soon as the syndrome is recognized, but can persist for several months after drug discontinuation if the syndrome fully develops. Reserpine withdrawal psychosis has been reported.

The depressive syndrome usually consists of melancholy, loss of self confidence, early morning awakening, loss of libido, and reduced appetite.

A case of reserpine withdrawal psychosis has been reported. This uncommon condition may be due to dopamine receptor supersensitivity, which develops during reserpine therapy.

Gastrointestinal

Due to unopposed parasympathetic activity produced by catecholamine depletion, reserpine increases gastrointestinal motility and secretory activity. Because of this, new diarrhea or worsening of existing diarrhea or increased salivation have been reported in 2% of patients. Increased appetite, abdominal pain, or vomiting have only rarely been reported.

Cardiovascular

Cardiovascular side effects include hypotension in 8% and bradycardia (and rare cases of syncope with bradycardia) in 3% of patients. A rare case of paroxysmal atrial tachycardia with block associated with reserpine in a patient who was not taking a digitalis preparation has been reported.

A woman with paroxysmal atrial tachycardia developed sinus pauses during reserpine therapy which were reproducible by carotid massage, except when isoproterenol was given. Reserpine is known to increase vagal tone and deplete cardiac catecholamines.

One patient, in a series of 231, had emergent hypertension, stroke, and thyrotoxic crisis. Reserpine 1 mg intramuscularly resulted in a blood pressure drop from 180/100 to an unmeasurable level. The patient recovered after isoproterenol therapy.

Genitourinary

Genitourinary complaints have been limited to impotence in approximately 5% of male patients.

Endocrine

Endocrinologic abnormalities are due to reserpine-induced hyperprolactinemia. Gynecomastia in men, breast engorgement in women, and pseudolactation have been reported.

Immunologic

A 79-year-old woman with hypertension, taking reserpine, potassium, HCTZ, and ibuprofen, developed fatigue, anorexia, fever, night sweats, and weight loss. Associated laboratory findings showed anemia, lymphocytosis, thrombocytopenia, IgA kappa paraproteinemia, positive ANA, and a positive Coombs' test. Bone marrow biopsy, lymphangiography, and lymph node biopsy showed bone marrow lymphocytosis, enlarged foamy abdominal lymph nodes with irregular filling, and angioimmunoblastic lymphadenopathy, respectively. Within four days after discontinuation of reserpine (her other medications were continued), the paraprotein level normalized and the platelet count rose. After an additional nine months of prednisone therapy, all signs and symptoms resolved.

Immunologic side effects are rare. One case of angioimmunoblastic lymphadenopathy has been associated with reserpine. In one study of 231 patients, only one case of a lupus-like syndrome was recorded. The patient had previously received hydralazine.

Oncologic

Oncologic concerns were raised after a large drug surveillance center in Boston reported an association between reserpine, a stimulator of prolactin, and breast cancer in 1974, which was partially, but not completely, confirmed in two similar centers in Europe. A critical review of the these studies elucidated several design flaws. Subsequent, controlled studies failed to show an association between reserpine and an increased incidence of breast carcinoma.