Generic Name

Prochlorperazine

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Classification

FDA Approved Indications

• Nausea and vomiting
• Vertigo
• Psychotic disorders

Mechanism of Action

Prochlorperazine blocks dopamine receptors in the brain's chemoreceptor trigger zone, thereby suppressing nausea and vomiting. It also exhibits antipsychotic properties by antagonizing dopaminergic transmission in the CNS.

Dosage and Administration

Adult: Typically 25 mg 3-4 times daily, adjusted based on response and tolerability.

Pediatric: Use is generally limited; dosing must be individualized and is often similar to adult doses, but safety in children younger than 2 is not established.

Geriatric: Start at lower doses due to increased sensitivity and risk of side effects.

Renal Impairment: Use with caution; dose adjustments may be necessary.

Hepatic Impairment: Use cautiously; monitor for increased effects.

Pharmacokinetics

Absorption: Well absorbed orally.

Distribution: Widely distributed in body tissues, crosses the blood-brain barrier and placenta.

Metabolism: Extensively metabolized in the liver.

Excretion: Primarily via urine, with some fecal excretion.

Half Life: approximately 10-30 hours, varies depending on individual factors.

Contraindications

• Complanned hypersensitivity to prochlorperazine or other phenothiazines
• Coma or CNS depression
• Severe liver disease

Precautions

• Use cautiously in elderly patients due to risk of neuroleptic malignant syndrome, tardive dyskinesia, and other extrapyramidal symptoms.
• Avoid use in Parkinson’s disease due to dopamine blockade.
• Use during pregnancy only if clearly needed; breastfeeding is generally not recommended.

Adverse Reactions - Common

• Drowsiness, dizziness (Common)
• Dry mouth (Common)
• Blurred vision (Common)

Adverse Reactions - Serious

• Extrapyramidal symptoms (Less common)
• Tardive dyskinesia (Rare)
• Neuroleptic malignant syndrome (Rare)
• QT prolongation and arrhythmias (Rare)
• Hyperglycemia, onset of diabetes mellitus (Rare)

Drug-Drug Interactions

• CNS depressants, alcohol (enhanced sedation)
• Other medications that prolong QT interval (increased risk of arrhythmias)
• Anticholinergic agents (potentiation of anticholinergic side effects)

Drug-Food Interactions

N/A

Drug-Herb Interactions

N/A

Nursing Implications

Patient/Family Teaching

• Advise patients to avoid alcohol and other CNS depressants.
• Instruct on the importance of reporting signs of movement disorders or allergic reactions.
• Warn about potential drowsiness—caution when driving or operating machinery.

Special Considerations

Black Box Warnings:

• Use can cause serious neuropsychiatric adverse reactions, including tardive dyskinesia, especially with long-term use.

Genetic Factors: None specifically established.

Lab Test Interference: May interfere with certain lab tests, such as those measuring catecholamines.

Overdose Management

Signs/Symptoms: Extrapyramidal symptoms, sedation, hypotension, respiratory depression, seizures.

Treatment: Supportive management; activate emesis if ingestion recent, provide IV fluids for hypotension, administer anticholinergic agents or bromocriptine for severe extrapyramidal symptoms, treat seizures appropriately.

Storage and Handling

Storage: Store at room temperature, away from light and moisture.

Stability: Stable under recommended storage conditions.