Comparative Pharmacology
Head-to-head clinical analysis: DIPHEN versus DIPHENHYDRAMINE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: DIPHEN versus DIPHENHYDRAMINE.
DIPHEN vs Diphenhydramine
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Diphenhydramine is a first-generation antihistamine that competitively antagonizes histamine at H1 receptors. It also exhibits anticholinergic, sedative, antiemetic, and local anesthetic effects.
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.
50 mg IV/IM every 4 hours as needed for nausea/vomiting; 25-50 mg PO every 4-6 hours as needed for nausea/vomiting or motion sickness; 25 mg PO 3-4 times daily for vertigo; 15.6-25 mg IM/IV for antiemetic in surgery; maximum 300 mg/day.
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).
MODERATE Risk
MODERATE Risk
Clinical Note
moderateDiphenoxylate + Torasemide
"The risk or severity of adverse effects can be increased when Diphenoxylate is combined with Torasemide."
Clinical Note
moderateDiphenoxylate + Etacrynic acid
"The risk or severity of adverse effects can be increased when Diphenoxylate is combined with Etacrynic acid."
Clinical Note
moderateDiphenoxylate + Furosemide
"The risk or severity of adverse effects can be increased when Diphenoxylate is combined with Furosemide."
Clinical Note
moderateTerminal elimination half-life is 22–72 hours (mean 30–40 hours); increases with hepatic disease or enzyme inhibitors.
Terminal elimination half-life 4-8 hours in adults; prolonged in hepatic impairment (up to 20 hours) and elderly.
Primarily hepatic metabolism; renal excretion of inactive metabolites accounts for ~70% of eliminated drug; biliary/fecal excretion accounts for ~30%.
Primarily renal (90-95% as metabolites, <5% unchanged). Minor biliary/fecal elimination (<5%).
Category C
Category C
Antihistamine
Antihistamine
Diphenoxylate + Bumetanide
"The risk or severity of adverse effects can be increased when Diphenoxylate is combined with Bumetanide."