Comparative Pharmacology
Head-to-head clinical analysis: DIPHEN versus LORATADINE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: DIPHEN versus LORATADINE.
DIPHEN vs LORATADINE
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.
Loratadine is a long-acting tricyclic antihistamine with selective peripheral H1-receptor antagonist activity. It inhibits histamine-induced vasodilation and bronchoconstriction.
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.
10 mg orally once daily
None Documented
None Documented
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.
Loratadine: 8-14 hours (mean ~10 hours). Active metabolite descarboethoxyloratadine: 17-24 hours (mean ~20 hours). Clinically, duration supports once-daily dosing.
Primarily hepatic metabolism; renal excretion of inactive metabolites accounts for ~70% of eliminated drug; biliary/fecal excretion accounts for ~30%.
Approximately 40% excreted in urine as metabolites (primarily descarboethoxyloratadine) and 40% in feces as metabolites; <1% excreted unchanged.
Category C
Category A/B
Antihistamine
Antihistamine
Diphenoxylate + Bumetanide
"The risk or severity of adverse effects can be increased when Diphenoxylate is combined with Bumetanide."