Comparative Pharmacology
Head-to-head clinical analysis: KETOTIFEN FUMARATE versus PROMETHAZINE HYDROCHLORIDE CODEINE PHOSPHATE.
Head-to-head clinical analysis: KETOTIFEN FUMARATE versus PROMETHAZINE HYDROCHLORIDE CODEINE PHOSPHATE.
KETOTIFEN FUMARATE vs PROMETHAZINE HYDROCHLORIDE; CODEINE PHOSPHATE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Antihistamine and mast cell stabilizer; inhibits release of histamine and other mediators from mast cells; also blocks histamine H1 receptors.
Promethazine is a phenothiazine derivative that acts as a histamine H1 receptor antagonist, antiemetic, and sedative via blockade of central and peripheral H1 receptors and antagonism of dopamine D2 receptors. Codeine is an opioid agonist that binds to mu-opioid receptors in the CNS, producing analgesia and cough suppression; it also has antitussive effects via central action.
1 mg orally twice daily; ophthalmic: 1 drop in each eye every 8-12 hours.
Promethazine hydrochloride 6.25-25 mg / codeine phosphate 10-20 mg (based on codeine component) orally every 4-6 hours as needed. Maximum codeine dose: 60 mg per dose, 120 mg per day.
None Documented
None Documented
Terminal half-life 12-24 hours (mean 18 hours); requires twice-daily dosing after initial titration.
Promethazine: 10-19 hours (terminal); Codeine: 2.4-4 hours (terminal), prolonged in hepatic impairment. Clinical context: Dosing interval typically 4-6 hours for codeine; promethazine accumulates with repeated dosing.
Renal (50-70% as conjugates, <2% unchanged), fecal (<10%), with enterohepatic circulation.
Promethazine: Renal (70-80% as metabolites, <1% unchanged); Codeine: Renal (70-90% as metabolites, 5-15% unchanged). Biliary/feces: Minor (<10% total).
Category A/B
Category A/B
Antihistamine / Mast Cell Stabilizer
Antihistamine / Antiemetic