Comparative Pharmacology
Head-to-head clinical analysis: DRIXORAL versus PROMETHAZINE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: DRIXORAL versus PROMETHAZINE.
DRIXORAL vs PROMETHAZINE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Drixoral is a combination product containing dexbrompheniramine maleate, a first-generation antihistamine that competitively antagonizes histamine at H1 receptor sites, and pseudoephedrine sulfate, a sympathomimetic amine that acts as a decongestant by stimulating alpha-adrenergic receptors in the respiratory tract mucosa, causing vasoconstriction and reducing nasal congestion.
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.
One pseudoephedrine 60 mg and dexbrompheniramine 2 mg tablet orally every 12 hours; maximum 2 tablets per 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
moderateDexbrompheniramine: 12-15h (prolonged in renal impairment). Pseudoephedrine: 5-8h (alkaline urine slows elimination, half-life up to 20h).
Terminal elimination half-life 9-16 hours; may be prolonged in hepatic impairment.
Drixoral contains dexbrompheniramine (renal: 30-50% unchanged, rest metabolites) and pseudoephedrine (renal: 70-90% unchanged, pH-dependent).
Renal (70-80% as metabolites, <1% unchanged); biliary/fecal minor.
Category C
Category A/B
Antihistamine/Decongestant
Antihistamine / Antiemetic
Promethazine + Clotrimazole
"The metabolism of Clotrimazole can be decreased when combined with Promethazine."