Comparative Pharmacology
Head-to-head clinical analysis: PROCHLORPERAZINE versus PROMETHAZINE VC W CODEINE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: PROCHLORPERAZINE versus PROMETHAZINE VC W CODEINE.
PROCHLORPERAZINE vs PROMETHAZINE VC W/ CODEINE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Prochlorperazine is a phenothiazine antipsychotic that acts as a dopamine D2 receptor antagonist in the chemoreceptor trigger zone (CTZ) and at high doses in the mesolimbic system. It also has anticholinergic and antiemetic effects.
Codeine is a prodrug converted to morphine, which acts as a mu-opioid receptor agonist inhibiting ascending pain pathways and altering pain perception. Promethazine is a phenothiazine derivative that antagonizes histamine H1 receptors, suppresses cough reflex via central action, and has anticholinergic, sedative, and antiemetic effects. Phenylephrine is a selective alpha-1 adrenergic receptor agonist causing vasoconstriction of nasal blood vessels, reducing congestion.
5-10 mg IM/IV every 3-4 hours as needed; or 5-10 mg PO 3-4 times daily; or 25 mg PR twice daily. Maximum IM/IV: 40 mg/day; PO: 40 mg/day.
1-2 tablets orally every 4-6 hours as needed for cough and congestion. Maximum 12 tablets in 24 hours.
None Documented
None Documented
Clinical Note
moderateProchlorperazine + Fluticasone propionate
"The risk or severity of adverse effects can be increased when Prochlorperazine is combined with Fluticasone propionate."
Clinical Note
moderateProchlorperazine + Haloperidol
"The metabolism of Haloperidol can be decreased when combined with Prochlorperazine."
Clinical Note
moderateProchlorperazine + Methylphenidate
"The risk or severity of adverse effects can be increased when Prochlorperazine is combined with Methylphenidate."
Clinical Note
moderateTerminal elimination half-life: 23-25 hours, with prolonged elimination in hepatic impairment.
Promethazine: 9-16 hours (range 7-20 hours) in adults; codeine: 2.5-3.5 hours (terminal) with clinical considerations for prolonged effects in hepatic impairment and CYP2D6 poor metabolizers.
Renal: 70-80% (as metabolites), Fecal: 20-30% (unchanged and metabolites), Biliary: 10-15% of dose excreted in bile.
Renal: 70-80% as unchanged promethazine and metabolites (including codeine and its glucuronides); biliary/fecal: 10-20%.
Category A/B
Category A/B
Typical Antipsychotic / Antiemetic
Antihistamine / Antiemetic
Prochlorperazine + Quinagolide
"The therapeutic efficacy of Quinagolide can be decreased when used in combination with Prochlorperazine."