Comparative Pharmacology
Head-to-head clinical analysis: COMPAZINE versus PROMETHAZINE DM.
Peer-Reviewed Evidence
Head-to-head clinical analysis: COMPAZINE versus PROMETHAZINE DM.
COMPAZINE vs PROMETHAZINE DM
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Dopamine D2 receptor antagonist in the chemoreceptor trigger zone; also blocks alpha-1 adrenergic, histamine H1, and muscarinic M1 receptors.
Promethazine is a phenothiazine derivative that acts as a histamine H1 receptor antagonist, antiemetic via blockade of dopamine D2 receptors in the chemoreceptor trigger zone, and sedative via central anticholinergic effects. Dextromethorphan is an NMDA receptor antagonist and sigma-1 receptor agonist, suppressing cough by central action on the cough center.
5-10 mg IM/IV every 3-4 hours as needed; or 25 mg PO/PR twice daily for severe nausea/vomiting.
2 teaspoonfuls (10 mL) orally every 4-6 hours, not to exceed 8 teaspoonfuls (40 mL) per 24 hours.
None Documented
None Documented
Terminal elimination half-life is approximately 23 hours (range 15-30 hours) after oral or intramuscular administration. Clinical context: requires multiple daily dosing for steady state.
16-19 hours (terminal); note: effect may last longer due to active metabolites and tissue binding
Renal (approximately 70% as metabolites, <1% unchanged), biliary/fecal (approximately 30%).
Renal (70-80% as metabolites, <1% unchanged); biliary/fecal (20-30%)
Category C
Category A/B
Antipsychotic (Phenothiazine) / Antiemetic
Antihistamine / Antiemetic