Compazine Vs. Zofran: Drug Comparison

Compazine^® is a brand-name medication that contains the active ingredient prochlorperazine. The information below is about prochlorperazine maleate tablets. According to the FDA, “Generic medicines use the same active ingredients as brand-name medicines and work the same way, so they have the same risks and benefits as the brand-name medicines.”

Prochlorperazine is a medication approved to treat nausea, vomiting, and mental health conditions such as schizophrenia and severe anxiety. It works by altering chemical signals in the brain to reduce these symptoms. Common side effects include drowsiness, dizziness, and blurred vision, and it may cause light sensitivity or dry mouth. Prochlorperazine carries warnings about the risk of tardive dyskinesia, a condition involving involuntary muscle movements, particularly with long-term use. It should be used cautiously in people with certain conditions, such as heart disease, glaucoma, or a history of seizures, as it may exacerbate these issues.

Zofran^® is a brand-name medication that contains the active ingredient ondansetron. The information below is about ondansetron hydrochloride tablets. According to the FDA, “Generic medicines use the same active ingredients as brand-name medicines and work the same way, so they have the same risks and benefits as the brand-name medicines.”

Ondansetron is a medication used to prevent nausea and vomiting by blocking serotonin receptors in the brain and gut, which are involved in triggering the vomiting reflex. Its FDA-approved indications include the prevention of nausea and vomiting associated with chemotherapy, radiation therapy, and surgery. Off-label uses may include managing nausea in pregnancy (morning sickness) and gastroenteritis. Ondansetron is available in several forms, including oral tablets, orally disintegrating tablets, oral solution, and intravenous injections. Common side effects include headaches, constipation, and dizziness, while serious risks include a rare heart rhythm disorder (QT prolongation). Caution is advised in patients with heart conditions or those taking other medications that affect the QT interval.

Phenothiazine

5-HT₃ receptor antagonist

Prochlorperazine is indicated for:

• Control of severe nausea and vomiting

• The treatment of schizophrenia

• The short-term treatment of generalized non-psychotic anxiety

Ondansetron is indicated for the prevention of:

• Nausea and vomiting associated with highly emetogenic cancer chemotherapy, including cisplatin greater than or equal to 50 mg/m²

• Nausea and vomiting associated with initial and repeat courses of moderately emetogenic cancer chemotherapy

• Nausea and vomiting associated with radiotherapy in patients receiving either total body irradiation, single high-dose fraction to the abdomen, or daily fractions to the abdomen

• Postoperative nausea and/or vomiting

• Typically taken orally three or four times daily

• Comes in 5 mg and 10 mg tablets

• Typically taken orally—see the full prescribing information for the recommended dosage in adults and pediatric

• Comes in 4 mg, 8 mg, and 24 mg tablets

Adverse reactions that may occur include:

• Drowsiness

• Dizziness

• Absence of menstrual period

• Blurred vision

• Skin reactions

• Low blood pressure

• Neuroleptic malignant syndrome

• Cholestatic jaundice

• Leukopenia and agranulocytosis

• Extrapyramidal symptoms

• Involuntary muscle contractions

• Motor restlessness

• Tardive dyskinesia

The most common adverse reactions in adults for the:

Prevention of chemotherapy-induced (≥5%) are:

• Headache

• Malaise/Fatigue

• Constipation

• Diarrhea

Prevention of radiation-induced nausea and vomiting (≥2%) are:

• Headache

• Constipation

• Diarrhea

Prevention of postoperative nausea and vomiting (≥9%) are:

• Headache

• Low levels of oxygen

• Do not use in patients with known hypersensitivity to phenothiazines

• Do not use in comatose states or in the presence of large amounts of central nervous system depressants (alcohol, barbiturates, narcotics, etc.)

• Do not use in pediatric surgery

• Do not use in pediatric patients under 2 years of age or under 20 lbs. Do not use in children for conditions for which dosage has not been established

• Drug interactions: Central nervous system depressants (e.g., alcohol, anesthetics, narcotics), oral anticoagulants, thiazide diuretics, propranolol, anticonvulsants

• Patients known to have hypersensitivity (e.g., anaphylaxis) to ondansetron or any components of the formulation

• Concomitant use of apomorphine

• Leukopenia, neutropenia, and agranulocytosis

• Tardive dyskinesia

• Neuroleptic malignant syndrome

• Prochlorperazine may impair mental and/or physical abilities, especially during the first few days of therapy

• Falls

• The antiemetic action of prochlorperazine may mask the signs and symptoms of overdosage of other drugs and may obscure the diagnosis and treatment of other conditions such as intestinal obstruction, brain tumor and Reye’s syndrome

• When prochlorperazine is used with cancer chemotherapeutic drugs, vomiting as a sign of the toxicity of these agents may be obscured by the antiemetic effect of prochlorperazine

• Because low blood pressure may occur, large doses and parenteral administration should be used cautiously in patients with impaired cardiovascular systems

• Aspiration of vomitus has occurred in a few post-surgical patients who have received prochlorperazine as an antiemetic

• Deep sleep, from which patients can be aroused, and coma have been reported, usually with overdosage

• Antipsychotic drugs elevate prolactin levels

• Chromosomal aberrations in spermatocytes and abnormal sperm have been demonstrated in rodents treated with certain antipsychotics

• As with all drugs which exert an anticholinergic effect, and/or cause mydriasis, prochlorperazine should be used with caution in patients with glaucoma

• Because phenothiazines may interfere with thermoregulatory mechanisms, use with caution in persons who will be exposed to extreme heat

• Phenothiazines can produce alpha-adrenergic blockade

• The presence of phenothiazines may produce false-positive phenylketonuria (PKU) test results

• Pregnancy: Safety for the use of prochlorperazine during pregnancy has not been established

• Breastfeeding: There is evidence that phenothiazines are excreted in the breast milk of nursing mothers. Caution should be exercised when prochlorperazine is administered to a nursing woman

• Hypersensitivity reactions, including anaphylaxis and bronchospasm

• QT interval prolongation and Torsade de pointes

• Serotonin syndrome

• Myocardial ischemia

• Masking of progressive ileus and/or gastric distension following abdominal surgery or chemotherapy-induced nausea and vomiting

WARNING: INCREASED MORTALITY IN ELDERLY PATIENTS WITH DEMENTIA-RELATED PSYCHOSIS

Elderly patients with dementia-related psychosis treated with antipsychotic drugs are at an increased risk of death. Analyses of seventeen placebo-controlled trials (modal duration of 10 weeks), largely in patients taking atypical antipsychotic drugs, revealed a risk of death in drug-treated patients of between 1.6 to 1.7 times the risk of death in placebo-treated patients. Over the course of a typical 10-week controlled trial, the rate of death in drug-treated patients was about 4.5% compared to a rate of about 2.6% in the placebo group. Although the causes of death were varied, most of the deaths appeared to be either cardiovascular (e.g., heart failure, sudden death) or infectious (e.g., pneumonia) in nature. Observational studies suggest that, similar to atypical antipsychotic drugs, treatment with conventional antipsychotic drugs may increase mortality. The extent to which the findings of increased mortality in observational studies may be attributed to the antipsychotic drug as opposed to some characteristic(s) of the patients is not clear. Prochlorperazine maleate is not approved for the treatment of patients with dementia-related psychosis.

*This information is from the prochlorperazine maleate label used by Ajanta Pharma USA Inc. See the Full Prescribing Information for more complete information. Prochlorperazine may also be the active ingredient in other medications, and this information may not be accurate for all medications that include the active ingredient prochlorperazine.

*This information is from the ondansetron hydrochloride label used by Aurobindo Pharma Limited. See the Full Prescribing Information for more complete information. This information may not be accurate for all medications that include the active ingredient ondansetron.