Comparative Pharmacology
Head-to-head clinical analysis: DIPHENHYDRAMINE versus KOVANAZE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: DIPHENHYDRAMINE versus KOVANAZE.
Diphenhydramine vs KOVANAZE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Inverse agonist at histamine H1 receptors, blocking histamine-mediated effects in blood vessels, respiratory smooth muscle, and GI tract; also anticholinergic by blocking muscarinic receptors and sedative via central H1 receptor antagonism.
KOVANAZE (norepinephrine and phenylephrine) is a combination of two vasopressors: norepinephrine, an α1-adrenergic receptor agonist with β1-adrenergic activity, and phenylephrine, a selective α1-adrenergic receptor agonist. Both agents cause vasoconstriction and increase blood pressure via activation of α1-adrenergic receptors on vascular smooth muscle.
25-50 mg orally or intramuscularly every 4-6 hours; maximum 300 mg/day. Intravenous administration: 10-50 mg slow IV push (max 25 mg/min).
Intravenous bolus of 1 mg/kg over 10 minutes, followed by intravenous infusion of 0.02 mg/kg/min for 4 hours, then 0.01 mg/kg/min for 20 hours.
None Documented
None Documented
Clinical Note
moderateDiphenhydramine + Deferasirox
"The serum concentration of Deferasirox can be increased when it is combined with Diphenhydramine."
Clinical Note
moderateDiphenhydramine + Fluticasone propionate
"The risk or severity of adverse effects can be increased when Diphenhydramine is combined with Fluticasone propionate."
Clinical Note
moderateDiphenhydramine + Tenofovir disoproxil
"The metabolism of Tenofovir disoproxil can be decreased when combined with Diphenhydramine."
Clinical Note
moderateTerminal elimination half-life 4-8 hours in adults; prolonged in hepatic impairment (up to 20 hours) and elderly.
Terminal elimination half-life: approximately 7-9 hours following nasal administration; clinical significance: supports twice-daily dosing regimen
Primarily renal (90-95% as metabolites, <5% unchanged). Minor biliary/fecal elimination (<5%).
Renal excretion of unchanged drug: ~20-30%; fecal/biliary elimination: minimal (<5%); remainder as metabolites
Category C
Category C
Antihistamine
Antihistamine + Corticosteroid Combination
Diphenhydramine + Sulfisoxazole
"The metabolism of Sulfisoxazole can be decreased when combined with Diphenhydramine."