Comparative Pharmacology
Head-to-head clinical analysis: DIPHENHYDRAMINE HYDROCHLORIDE PRESERVATIVE FREE versus HYDRAMINE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: DIPHENHYDRAMINE HYDROCHLORIDE PRESERVATIVE FREE versus HYDRAMINE.
DIPHENHYDRAMINE HYDROCHLORIDE PRESERVATIVE FREE vs HYDRAMINE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Competitive antagonist of histamine H1 receptors; centrally acting anticholinergic agent that inhibits acetylcholine muscarinic receptors.
Antagonist of histamine H1 receptors, preventing histamine-mediated responses such as vasodilation, bronchoconstriction, and increased capillary permeability.
25 to 50 mg intravenously or intramuscularly every 4 to 6 hours as needed; maximum 400 mg per day.
50-100 mg IV/IM every 4-6 hours, maximum 400 mg per day. Also available as 50 mg oral tablets.
None Documented
None Documented
Terminal elimination half-life: 4-10 hours (mean ~8 hours); prolonged in hepatic impairment or elderly (up to 20 hours).
Clinical Note
moderateDiphenhydramine + Deferasirox
"The serum concentration of Deferasirox can be increased when it is combined with Diphenhydramine."
Clinical Note
moderateDiphenhydramine + Fluticasone propionate
"The risk or severity of adverse effects can be increased when Diphenhydramine is combined with Fluticasone propionate."
Clinical Note
moderateDiphenhydramine + Tenofovir disoproxil
"The metabolism of Tenofovir disoproxil can be decreased when combined with Diphenhydramine."
Clinical Note
moderateTerminal elimination half-life 5.7 hours, range 4.2-7.7 hours; prolonged in hepatic impairment (up to 15 hours in cirrhosis)
Primarily renal as inactive metabolites; ~60% of a dose appears in urine as metabolites, with <5% unchanged. Minor biliary/fecal elimination (<10%).
Primarily renal (95%) as metabolites; <5% unchanged; 5% fecal
Category A/B
Category C
Antihistamine
Antihistamine
Diphenhydramine + Sulfisoxazole
"The metabolism of Sulfisoxazole can be decreased when combined with Diphenhydramine."