Comparative Pharmacology
Head-to-head clinical analysis: BENADRYL PRESERVATIVE FREE versus CYPROHEPTADINE HYDROCHLORIDE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: BENADRYL PRESERVATIVE FREE versus CYPROHEPTADINE HYDROCHLORIDE.
BENADRYL PRESERVATIVE FREE vs CYPROHEPTADINE HYDROCHLORIDE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Diphenhydramine competitively antagonizes histamine at H1-receptors on effector cells, leading to relief of allergic symptoms. It also possesses anticholinergic, antiemetic, sedative, and local anesthetic effects.
Cyproheptadine is a potent antihistamine (H1 receptor antagonist) and antiserotonergic agent (5-HT2 receptor antagonist). It also exhibits weak anticholinergic and sedative properties. It blocks histamine-mediated vasodilation, increased capillary permeability, and pruritus, as well as serotonin-mediated effects on appetite and mood.
25-50 mg IV/IM every 4-6 hours as needed; maximum single dose 100 mg, maximum daily dose 400 mg.
4 mg orally three times daily; range 4-20 mg/day, not to exceed 0.5 mg/kg/day
None Documented
None Documented
Terminal elimination half-life: 4-8 hours (mean ~5 hours). Prolonged in hepatic impairment (up to 2-fold) and elderly (7-12 hours).
Terminal half-life approximately 8–16 hours in adults; may be prolonged in elderly or hepatic impairment.
Primarily renal (90% as metabolites and unchanged drug); ~1% excreted in feces via bile. Unchanged diphenhydramine accounts for <5% of urinary recovery.
Primarily renal (appreciable unchanged drug and metabolites); biliary/fecal elimination minor (<5%).
Category C
Category A/B
Antihistamine
Antihistamine