Comparative Pharmacology
Head-to-head clinical analysis: DISOPHROL versus PROMETHAZINE DM.
Peer-Reviewed Evidence
Head-to-head clinical analysis: DISOPHROL versus PROMETHAZINE DM.
DISOPHROL vs PROMETHAZINE DM
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 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.
1 tablet (6 mg dexbrompheniramine maleate / 60 mg pseudoephedrine sulfate) orally every 4-6 hours; not to exceed 4 tablets in 24 hours.
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 3-4 hours in adults; in renal impairment, half-life may be prolonged up to 8-12 hours requiring dose adjustment.
16-19 hours (terminal); note: effect may last longer due to active metabolites and tissue binding
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 (70-80% as metabolites, <1% unchanged); biliary/fecal (20-30%)
Category C
Category A/B
Antihistamine/Decongestant Combination
Antihistamine / Antiemetic