Comparative Pharmacology
Head-to-head clinical analysis: HISTAFED versus VISTARIL.
Peer-Reviewed Evidence
Head-to-head clinical analysis: HISTAFED versus VISTARIL.
HISTAFED vs VISTARIL
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
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.
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.
60 mg orally every 4 to 6 hours as needed; maximum 360 mg per day.
Oral: 50-100 mg 4 times daily; IM: 25-100 mg every 4-6 hours as needed.
None Documented
None Documented
3-4 hours for pseudoephedrine component; shorter in children (2-3 h), prolonged in renal impairment
Terminal elimination half-life: 20-25 hours in adults; prolonged in hepatic impairment or elderly; steady-state achieved in ~4-5 days.
Renal (approximately 65% as unchanged drug and metabolites), biliary/fecal (35%)
Primarily hepatic metabolism; <1% excreted unchanged in urine; biliary/fecal elimination of metabolites accounts for approximately 50-60% of total clearance.
Category C
Category C
Antihistamine/Decongestant Combination
Antihistamine