Comparative Pharmacology
Head-to-head clinical analysis: ATARAX versus HISTAFED.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ATARAX versus HISTAFED.
ATARAX vs HISTAFED
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Hydroxyzine is a piperazine derivative with antihistaminic (H1-receptor antagonist) and anticholinergic properties; also exhibits sedative, anxiolytic, and antiemetic effects due to suppression of activity in subcortical areas of the CNS.
HISTAFED is a combination of pseudoephedrine, a sympathomimetic amine that acts as a decongestant by stimulating alpha-adrenergic receptors in the nasal mucosa causing vasoconstriction, and triprolidine, a first-generation antihistamine that competes with histamine for H1-receptor sites on effector cells in the gastrointestinal tract, blood vessels, and respiratory tract, thereby preventing histamine-mediated effects.
25 mg orally 3-4 times daily; maximum 100 mg per day. Also available as 50 mg intramuscular injection every 4-6 hours.
60 mg orally every 4 to 6 hours as needed; maximum 360 mg per day.
None Documented
None Documented
Terminal elimination half-life is approximately 20-25 hours in healthy adults; may be prolonged in elderly, hepatic impairment, or renal insufficiency (up to 30-40 hours); steady-state achieved within 3-4 days.
3-4 hours for pseudoephedrine component; shorter in children (2-3 h), prolonged in renal impairment
Primarily hepatic metabolism via CYP3A4 and CYP2D6; renal excretion of metabolites accounts for approximately 70-80% of the dose, with less than 1% excreted unchanged; fecal excretion is about 10-15%.
Renal (approximately 65% as unchanged drug and metabolites), biliary/fecal (35%)
Category C
Category C
Antihistamine
Antihistamine/Decongestant Combination