Comparative Pharmacology
Head-to-head clinical analysis: DISOPHROL versus PROMETHAZINE HYDROCHLORIDE AND CODEINE PHOSPHATE.
Head-to-head clinical analysis: DISOPHROL versus PROMETHAZINE HYDROCHLORIDE AND CODEINE PHOSPHATE.
DISOPHROL vs PROMETHAZINE HYDROCHLORIDE AND CODEINE PHOSPHATE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Disophrol is a combination of dexbrompheniramine, a first-generation antihistamine that blocks H1 receptors, and pseudoephedrine, a sympathomimetic amine that stimulates alpha-adrenergic receptors causing vasoconstriction.
Promethazine is a phenothiazine derivative that antagonizes histamine H1 receptors, reducing allergic symptoms; it also has anticholinergic, antiemetic, and sedative effects. Codeine is an opioid agonist at mu-opioid receptors, producing analgesia and antitussive effects by central mechanisms.
1 tablet (6 mg dexbrompheniramine maleate / 60 mg pseudoephedrine sulfate) orally every 4-6 hours; not to exceed 4 tablets in 24 hours.
Adults: 5 mL (containing promethazine 6.25 mg and codeine 10 mg) orally every 4-6 hours as needed; maximum 30 mL per day.
None Documented
None Documented
Terminal elimination half-life is 3-4 hours in adults; in renal impairment, half-life may be prolonged up to 8-12 hours requiring dose adjustment.
Promethazine: 10-19 hours (range 5-30h); Codeine: 2.5-4 hours (rapidly metabolized); Clinical context: sustained antitussive effect from codeine despite short half-life. Half-life of promethazine extends with hepatic impairment.
Renal excretion of unchanged drug and metabolites; approximately 60-70% of a dose eliminated in urine as unchanged drug and glucuronide conjugates, with <10% in feces.
Renal: Codeine and metabolites ~90% (free and conjugated), Promethazine and metabolites primarily renal; minor biliary/fecal (<5% for codeine, ~6% for promethazine).
Category C
Category A/B
Antihistamine/Decongestant Combination
Antihistamine / Antiemetic