Comparative Pharmacology
Head-to-head clinical analysis: HYDROXYZINE versus ZYRTEC.
Peer-Reviewed Evidence
Head-to-head clinical analysis: HYDROXYZINE versus ZYRTEC.
HYDROXYZINE vs ZYRTEC
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Hydroxyzine is a first-generation antihistamine that acts as a competitive antagonist at histamine H1 receptors in the gastrointestinal tract, blood vessels, and respiratory tract. It also exhibits sedative, anxiolytic, and antiemetic properties, possibly through central nervous system depression and anticholinergic effects.
Selective histamine H1-receptor antagonist; inhibits histamine release from mast cells and basophils.
25-100 mg orally 3-4 times daily; 50-100 mg IM every 4-6 hours as needed. Maximum oral dose: 600 mg/day in divided doses.
5-10 mg orally once daily; maximum 10 mg/day.
None Documented
None Documented
Terminal elimination half-life: 14-25 hours (mean ~20 h). In elderly or hepatic impairment, may be prolonged; antihistamine effect persists beyond half-life due to active metabolite.
Clinical Note
moderateHydroxyzine + Venlafaxine
"The risk or severity of adverse effects can be increased when Hydroxyzine is combined with Venlafaxine."
Clinical Note
moderateHydroxyzine + Nefazodone
"The risk or severity of adverse effects can be increased when Hydroxyzine is combined with Nefazodone."
Clinical Note
moderateHydroxyzine + Mifepristone
"Hydroxyzine may increase the QTc-prolonging activities of Mifepristone."
Clinical Note
moderateHydroxyzine + Fesoterodine
Terminal elimination half-life is approximately 8-11 hours in healthy adults, prolonged in renal impairment (e.g., up to 20 hours in moderate renal failure).
Renal: approximately 70% as metabolites, less than 1% unchanged. Fecal/biliary: minor. Cetirizine (active metabolite) also renally eliminated.
Cetirizine is primarily excreted unchanged in urine (approximately 70% renal elimination) and feces (about 10%).
Category A/B
Category C
Antihistamine
Antihistamine
"The serum concentration of the active metabolites of Fesoterodine can be increased when Fesoterodine is used in combination with Hydroxyzine."