Comparative Pharmacology
Head-to-head clinical analysis: DIPHENHYDRAMINE HYDROCHLORIDE versus XYZAL.
Peer-Reviewed Evidence
Head-to-head clinical analysis: DIPHENHYDRAMINE HYDROCHLORIDE versus XYZAL.
DIPHENHYDRAMINE HYDROCHLORIDE vs XYZAL
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Competitive antagonist of histamine H1 receptors, reducing allergic symptoms; also exerts anticholinergic, sedative, and antiemetic effects via central and peripheral receptor blockade.
Levocetirizine is a selective histamine H1-receptor antagonist; it inhibits the histamine-mediated responses in allergic conditions.
25-50 mg orally or intramuscularly every 4-6 hours as needed; maximum 300 mg per day.
5 mg orally once daily in the evening.
None Documented
None Documented
Terminal elimination half-life 4–10 hours (mean ~7 hours); prolonged in elderly, hepatic impairment, and with CYP2D6 poor metabolizers.
Terminal elimination half-life is approximately 7 hours in healthy adults; prolonged to 8–11 hours in elderly and in renal impairment.
Renal elimination of metabolites accounts for ~60% of the dose; <5% excreted unchanged. Fecal excretion ~40% via bile.
Approximately 84% of a dose is excreted renally as unchanged drug; 12% in feces via biliary elimination.
Category A/B
Category C
Antihistamine
Antihistamine