Comparative Pharmacology
Head-to-head clinical analysis: HYDROXYZINE versus PBZ SR.
Peer-Reviewed Evidence
Head-to-head clinical analysis: HYDROXYZINE versus PBZ SR.
HYDROXYZINE vs PBZ-SR
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.
Antihistamine; H1-receptor antagonist that competes with histamine for binding at H1 receptor sites, thereby preventing histamine-mediated allergic responses.
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.
100-200 mg orally every 12 hours; maximum 400 mg/day.
None Documented
None Documented
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: 14-25 hours (mean ~20 h). In elderly or hepatic impairment, may be prolonged; antihistamine effect persists beyond half-life due to active metabolite.
Terminal elimination half-life is approximately 4-6 hours in adults with normal renal function; clinically relevant dosing every 4-6 hours is recommended.
Renal: approximately 70% as metabolites, less than 1% unchanged. Fecal/biliary: minor. Cetirizine (active metabolite) also renally eliminated.
Primarily renal excretion (80-90% as unchanged drug) via glomerular filtration and tubular secretion. Biliary/fecal excretion accounts for approximately 5-10%.
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."