Comparative Pharmacology
Head-to-head clinical analysis: PROMETHAZINE versus SEMPREX D.
Peer-Reviewed Evidence
Head-to-head clinical analysis: PROMETHAZINE versus SEMPREX D.
PROMETHAZINE vs SEMPREX-D
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
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.
SEMPREX-D combines acrivastine, a histamine H1 receptor antagonist, and pseudoephedrine, a sympathomimetic amine vasoconstrictor. Acrivastine blocks peripheral histamine-mediated effects, while pseudoephedrine constricts nasal blood vessels to reduce congestion.
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.
1 capsule orally every 12 hours; each capsule contains acrivastine 8 mg and pseudoephedrine 60 mg.
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 9-16 hours; may be prolonged in hepatic impairment.
Terminal elimination half-life is approximately 8-12 hours, allowing twice-daily dosing.
Renal (70-80% as metabolites, <1% unchanged); biliary/fecal minor.
Renal (approx. 60% as unchanged drug and metabolites), biliary/fecal (approx. 40%).
Category A/B
Category C
Antihistamine / Antiemetic
Antihistamine/Decongestant Combination
Promethazine + Clotrimazole
"The metabolism of Clotrimazole can be decreased when combined with Promethazine."