Comparative Pharmacology
Head-to-head clinical analysis: PHENYLEPHRINE HYDROCHLORIDE AND PROMETHAZINE HYDROCHLORIDE versus PROCHLORPERAZINE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: PHENYLEPHRINE HYDROCHLORIDE AND PROMETHAZINE HYDROCHLORIDE versus PROCHLORPERAZINE.
PHENYLEPHRINE HYDROCHLORIDE AND PROMETHAZINE HYDROCHLORIDE vs PROCHLORPERAZINE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Phenylephrine is a selective alpha-1 adrenergic receptor agonist causing vasoconstriction; promethazine is a phenothiazine derivative that blocks histamine H1 receptors and has anticholinergic, antiemetic, and sedative effects.
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.
IV: 0.1-0.5 mg phenylephrine and 12.5-25 mg promethazine as a single dose.
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.
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
moderatePhenylephrine: 2-3 hours (terminal). Promethazine: 10-14 hours (terminal in adults; prolonged in elderly and hepatic impairment).
Terminal elimination half-life: 23-25 hours, with prolonged elimination in hepatic impairment.
Phenylephrine: renal (80% as unchanged drug and sulfate conjugates). Promethazine: renal (70-80% as metabolites and unchanged drug), fecal (20-30%).
Renal: 70-80% (as metabolites), Fecal: 20-30% (unchanged and metabolites), Biliary: 10-15% of dose excreted in bile.
Category A/B
Category A/B
Antihistamine / Antiemetic
Typical Antipsychotic / Antiemetic
Prochlorperazine + Quinagolide
"The therapeutic efficacy of Quinagolide can be decreased when used in combination with Prochlorperazine."