Pharmacology of Prochlorperazine

Study Notes

Indications

Treats psychotic disorders, including schizophrenia.
Manages anxiety symptoms.
Controls severe nausea and vomiting.

Contraindications

Not for use in cases of hypersensitivity or coma.
Avoid with severe CNS depression and large concurrent use of CNS depressants.
Caution in poorly controlled seizure disorders and subcortical brain damage.
Not recommended for children under 2 years or weighing less than 9 kg.
Should not be used for postoperative nausea/vomiting after pediatric surgery.

Mechanism of Action

Functions as an antipsychotic by blocking mesolimbic dopamine receptors and alpha-adrenergic receptors (D1 and D2).
Acts as an antiemetic by exerting antidopaminergic effects, blocking dopamine receptors in the brain and vagus nerve in the gastrointestinal tract.

Trade and Generic Name

Trade name: Compazine.
Generic name: prochlorperazine.

Dosage

For severe nausea and vomiting:
- Oral: Immediate-release (5-10 mg every 6-8 hours), Extended-release (10 mg every 12 hours or 15 mg every morning).
- Suppository: 25 mg every 12 hours.
- Intramuscular (IM): 5-10 mg every 3-4 hours (max 40 mg/day).
- Intravenous (IV): 2.5-10 mg every 3-4 hours (max 10 mg/day).
For psychosis:
- Oral: 5-10 mg every 6-8 hours, with slow dose titration (max 150 mg/day).
- IM: 10-20 mg every 2-4 hours (rarely need 3-4 doses).

Administration

Available in oral, intramuscular (IM), intravenous (IV), and suppository forms.

Adverse Reactions and Side Effects

Common side effects include drowsiness, dizziness, amenorrhea (absence of menstruation), blurred vision, skin reactions, and hypotension.

Drug Classification

Classified as antiemetic agents, antipsychotics, and phenothiazines.

Description

This quiz covers the indications, contraindications, mechanisms of action, and dosage of Prochlorperazine, an antipsychotic and antiemetic drug. Test your understanding of its clinical uses and safety considerations.