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  3. /Diphenhydramine

Diphenhydramine

Benadryl, ZzzQuil, Sominex, Percogesic Reformulated Jan 2011, Wal-Dryl, Compoz, Wal-Dryl Childrens, Wal-Dryl-D, Wal-Dryl Allergy, Wal-Som Maximum Strength, Nytol, Banophen Cream, Sleep-Eze, Unisom Sleep, Scot-Tussin Allergy, Panadol PM, Rest Simply, Kids-Eeze Allergy, Acetadryl, Dermamycin, Vetadryl, Wal-Sleep Z, ZZZ Sleep, Wal-Som, Z-Sleep, Aleve PM, Excedrin PM Triple Action, Wal-Dryl PE, Somnapure, The Itch Eraser, Vanamine, Dormin, Benadryl Allergy Plus Congestion, Banophen, Diphedryl, Diphenhist, Doans PM, Excedrin PM, Genahist, Calagel Reformulated Jun 2019, Legatrin PM, Siladryl, Sleepinal, Pediaclear Cough, Twilite, Tylenol PM, Unisom with Pain Relief, Tact, Simply Sleep, Benadryl Itch Stopping, Benadryl-D Allergy and Sinus, Buckley's Bedtime Formula, Calagel, Tekral, Motrin PM

Antihistamine • First-generation H1 antihistamine

Premium
CNS Depressant

Half-life

2.4-9.3 hours

Protein Binding

Metabolized By

CYP2D6

External

Drugs.com

Mechanism of Action

Non-selective H1 antagonist with significant anticholinergic and CNS effects

Indications(5)

Non-small Cell Lung Cancer (NSCLC)GVHDLymphomaPeripheral T Cell LymphomaAngioimmunoblastic T-cell Lymphoma

Classification

Drug Class

Antihistamine

Subclass

First-generation H1 antihistamine

Brand Names

BenadrylZzzQuilSominexPercogesic Reformulated Jan 2011Wal-DrylCompozWal-Dryl ChildrensWal-Dryl-DWal-Dryl AllergyWal-Som Maximum StrengthNytolBanophen CreamSleep-EzeUnisom SleepScot-Tussin AllergyPanadol PMRest SimplyKids-Eeze AllergyAcetadrylDermamycinVetadrylWal-Sleep ZZZZ SleepWal-SomZ-SleepAleve PMExcedrin PM Triple ActionWal-Dryl PESomnapureThe Itch EraserVanamineDorminBenadryl Allergy Plus CongestionBanophenDiphedrylDiphenhistDoans PMExcedrin PMGenahistCalagel Reformulated Jun 2019Legatrin PMSiladrylSleepinalPediaclear CoughTwiliteTylenol PMUnisom with Pain ReliefTactSimply SleepBenadryl Itch StoppingBenadryl-D Allergy and SinusBuckley's Bedtime FormulaCalagelTekralMotrin PM

Key Properties

Half-life

2.4-9.3 hours

Time for plasma concentration to decrease by 50%

Protein Binding

—

Fraction bound to plasma proteins

Therapeutic Index

Wide

Margin between therapeutic and toxic doses

Not a substitute for clinical judgement
Diphenhydramine Drug Profile | PharmaGraphX