Comparative Pharmacology
Head-to-head clinical analysis: AZELASTINE HYDROCHLORIDE versus HYDRAMINE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: AZELASTINE HYDROCHLORIDE versus HYDRAMINE.
AZELASTINE HYDROCHLORIDE vs HYDRAMINE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Azelastine hydrochloride is a phthalazinone derivative that exerts its effect by competitively inhibiting histamine at the H1 receptor site. It also stabilizes mast cells, reducing the release of inflammatory mediators such as histamine, leukotrienes, and cytokines. This dual action provides both antihistaminic and anti-inflammatory effects.
Antagonist of histamine H1 receptors, preventing histamine-mediated responses such as vasodilation, bronchoconstriction, and increased capillary permeability.
1 spray (137 mcg) per nostril twice daily; ophthalmic: 1 drop in affected eye(s) twice daily.
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
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 is approximately 22 hours (range 20–25 hours) following oral administration, supporting twice-daily dosing. For ophthalmic and intranasal routes, systemic half-life is similar due to absorption.
Terminal elimination half-life 5.7 hours, range 4.2-7.7 hours; prolonged in hepatic impairment (up to 15 hours in cirrhosis)
Approximately 75% of the dose is excreted in feces as unchanged drug and metabolites; about 25% is excreted renally, with less than 10% as unchanged drug.
Primarily renal (95%) as metabolites; <5% unchanged; 5% fecal
Category C
Category C
Antihistamine
Antihistamine
Diphenhydramine + Sulfisoxazole
"The metabolism of Sulfisoxazole can be decreased when combined with Diphenhydramine."