Acetaminophen and diphenhydramine:

U.S. BRAND NAMES — Excedrin® P.M. [OTC]; Goody's PM® [OTC]; Legatrin PM® [OTC]; Percogesic® Extra Strength [OTC]; Tylenol® PM [OTC]; Tylenol® Severe Allergy [OTC]
PHARMACOLOGIC CATEGORY Analgesic, Miscellaneous
DOSING: ADULTS — Insomnia and pain: Oral: Adults: 50 mg of diphenhydramine HCl (76 mg diphenhydramine citrate) at bedtime or as directed by physician; do not exceed recommended dosage
DOSING: PEDIATRIC — Not for use in children <12 years of age.
DOSING: ELDERLY — Refer to adult dosing.
DOSING: HEPATIC IMPAIRMENT — Use with caution. Limited, low-dose therapy is usually well tolerated in hepatic disease/cirrhosis; however, cases of hepatotoxicity at daily acetaminophen dosages <4 g/day have been reported. Avoid chronic use in hepatic impairment.
DOSAGE FORMS — Excipient information presented when available (limited, particularly for generics); consult specific product labeling.
Caplet: Acetaminophen 500 mg and diphenhydramine hydrochloride 25 mg Excedrin® P.M.: Acetaminophen 500 mg and diphenhydramine citrate 38 mg Legatrin PM®: Acetaminophen 500 mg and diphenhydramine hydrochloride 50 mg Percogesic® Extra Strength: Acetaminophen 500 mg and diphenhydramine hydrochloride 25 mg Tylenol® PM: Acetaminophen 500 mg and diphenhydramine hydrochloride 25 mg [also available in vanilla caplets] Tylenol® Severe Allergy: Acetaminophen 500 mg and diphenhydramine hydrochloride 12.5 mg
Gelcap: Tylenol® PM: Acetaminophen 500 mg and diphenhydramine hydrochloride 25 mg
Geltab: Acetaminophen 500 mg and diphenhydramine hydrochloride 25 mg Excedrin® P.M.: Acetaminophen 500 mg and diphenhydramine citrate 38 mg Tylenol® PM: Acetaminophen 500 mg and diphenhydramine hydrochloride 25 mg
Liquid: Tylenol® PM: Acetaminophen 500 mg and diphenhydramine hydrochloride 25 mg per 15 mL (240 mL) [contains sodium benzoate; vanilla flavor]
Powder for oral solution: Goody's PM®: Acetaminophen 500 mg and diphenhydramine citrate 38 mg [contains potassium 41.9 mg and sodium 3.15 mg per powder]
Tablet: Acetaminophen 500 mg and diphenhydramine hydrochloride 25 mg Excedrin® P.M.: Acetaminophen 500 mg and diphenhydramine citrate 38 mg
DOSAGE FORMS: CONCISE Caplet: Acetaminophen 500 mg and diphenhydramine 25 mg Excedrin® P.M. [OTC]: Acetaminophen 500 mg and diphenhydramine 38 mg Legatrin PM® [OTC]: Acetaminophen 500 mg and diphenhydramine 50 mg Percogesic® Extra Strength [OTC], Tylenol® PM [OTC]: Acetaminophen 500 mg and diphenhydramine 25 mg Tylenol® Severe Allergy [OTC]: Acetaminophen 500 mg and diphenhydramine 12.5 mg
Gelcap: Tylenol® PM [OTC]: Acetaminophen 500 mg and diphenhydramine 25 mg
Geltab: Acetaminophen 500 mg and diphenhydramine 25 mg Excedrin® P.M. [OTC]: Acetaminophen 500 mg and diphenhydramine 38 mg Tylenol® PM [OTC]: Acetaminophen 500 mg and diphenhydramine 25 mg
Liquid: Tylenol® PM [OTC]: Acetaminophen 500 mg and diphenhydramine 25 mg per 15 mL
Powder for oral solution: Goody's PM® [OTC]: Acetaminophen 500 mg and diphenhydramine 38 mg
Tablet: Acetaminophen 500 mg and diphenhydramine 25 mg Excedrin® P.M. [OTC]: Acetaminophen 500 mg and diphenhydramine 38 mg
GENERIC EQUIVALENT AVAILABLE — Yes: Excludes gelcap, powder, and liquid
USE — Aid in the relief of insomnia accompanied by minor pain
ADVERSE REACTIONS SIGNIFICANT — See individual agents.
DRUG INTERACTIONS Acetaminophen: Substrate (minor) of CYP1A2, 2A6, 2C9, 2D6, 2E1, 3A4; Inhibits CYP3A4 (weak)
Diphenhydramine: Inhibits CYP2D6 (moderate)
Also see individual agents.
ETHANOL / NUTRITION / HERB INTERACTIONS — Ethanol: Excessive intake of ethanol may increase the risk of acetaminophen-induced hepatotoxicity. Avoid ethanol or limit to <3 drinks/day.
PHARMACODYNAMICS / KINETICS — See individual agents.