Comparative Pharmacology
Head-to-head clinical analysis: DISOPHROL versus PROMETHAZINE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: DISOPHROL versus PROMETHAZINE.
DISOPHROL vs PROMETHAZINE
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 potent histamine H1 receptor antagonist, thereby blocking the effects of histamine. It also has central anticholinergic, antiemetic, and sedative properties, likely mediated through antagonism at muscarinic, dopamine D2, and serotonin receptors in the brain.
1 tablet (6 mg dexbrompheniramine maleate / 60 mg pseudoephedrine sulfate) orally every 4-6 hours; not to exceed 4 tablets in 24 hours.
12.5-25 mg IM or IV every 4-6 hours; also 25 mg PO or PR every 6-8 hours. Maximum 100 mg/day.
None Documented
None Documented
Clinical Note
moderatePromethazine + Risedronic acid
"Promethazine can cause an increase in the absorption of Risedronic acid resulting in an increased serum concentration and potentially a worsening of adverse effects."
Clinical Note
moderatePromethazine + Methylphenidate
"Promethazine can cause an increase in the absorption of Methylphenidate resulting in an increased serum concentration and potentially a worsening of adverse effects."
Clinical Note
moderatePromethazine + Artesunate
"The serum concentration of Artesunate can be increased when it is combined with Promethazine."
Clinical Note
moderateTerminal 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.
Terminal elimination half-life 9-16 hours; may be prolonged in 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 (70-80% as metabolites, <1% unchanged); biliary/fecal minor.
Category C
Category A/B
Antihistamine/Decongestant Combination
Antihistamine / Antiemetic
Promethazine + Clotrimazole
"The metabolism of Clotrimazole can be decreased when combined with Promethazine."