Comparative Pharmacology
Head-to-head clinical analysis: VISTARIL versus XYZAL.
Peer-Reviewed Evidence
Head-to-head clinical analysis: VISTARIL versus XYZAL.
VISTARIL vs XYZAL
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Hydroxyzine is a piperazine derivative antihistamine that acts as a competitive antagonist of histamine H1 receptors, thereby suppressing histamine activity in the subcortical area of the central nervous system. It also has anxiolytic, sedative, antiemetic, and antispasmodic effects.
Levocetirizine is a selective histamine H1-receptor antagonist; it inhibits the histamine-mediated responses in allergic conditions.
Oral: 50-100 mg 4 times daily; IM: 25-100 mg every 4-6 hours as needed.
5 mg orally once daily in the evening.
None Documented
None Documented
Terminal elimination half-life: 20-25 hours in adults; prolonged in hepatic impairment or elderly; steady-state achieved in ~4-5 days.
Terminal elimination half-life is approximately 7 hours in healthy adults; prolonged to 8–11 hours in elderly and in renal impairment.
Primarily hepatic metabolism; <1% excreted unchanged in urine; biliary/fecal elimination of metabolites accounts for approximately 50-60% of total clearance.
Approximately 84% of a dose is excreted renally as unchanged drug; 12% in feces via biliary elimination.
Category C
Category C
Antihistamine
Antihistamine