DiphenhydrAMINE Hydrochloride(dye fen hye’ dra meen)
Oral: Allerdryl (CAN), AllerMax Caplets, Banophen, Banophen Allergy, Benadryl Allergy, Diphen AF, Diphenhist, Diphenhist Captabs, Genahist, Siladryl
Oral prescription preparations: Benadryl
Parenteral preparations: Benadryl
PREGNANCY CATEGORY B
Drug Classes
Antihistamine
Anti–motion-sickness drug
Antiparkinsonian
Cough suppressant
Sedative-hypnotic
Therapeutic Actions
Competitively blocks the effects of histamine at H1-receptor sites, has atropine-like, antipruritic, and sedative effects.
Indications
Relief of symptoms associated with perennial and seasonal allergic rhinitis; vasomotor rhinitis; allergic conjunctivitis; mild, uncomplicated urticaria and angioedema; amelioration of allergic reactions to blood or plasma; dermatographism; adjunctive therapy in anaphylactic reactions
Active and prophylactic treatment of motion sickness
Nighttime sleep aid
Parkinsonism (including drug-induced parkinsonism and extrapyramidal reactions), in the elderly intolerant of more potent drugs, for milder forms of the disorder in other age groups, and in combination with centrally acting anticholinergic antiparkinsonian drugs
Syrup formulation: Suppression of cough due to colds or allergy
Contraindications and Cautions
Contraindicated with allergy to antihistamines, third trimester of pregnancy, lactation.
Use cautiously with narrow-angle glaucoma, stenosing peptic ulcer, symptomatic prostatic hypertrophy, asthmatic attack, bladder neck obstruction, pyloroduodenal obstruction, pregnancy; elderly patients who may be sensitive to anticholinergic effects.
Available Forms
Capsule soft gels—25 mg; capsules—25, 50 mg; tablets—25, 50 mg; chewable tablets—12.5 mg; elixir—12.5 mg/5 mL; syrup—12.5 mg/5 mL; liquid—12.5 mg/5 mL; injection—50 mg/mL; solution—12.5 mg/5 mL
Dosages
Adults
Oral
25–50 mg every 4–6 hr PO, not to exceed 300 mg/24 hr.
Motion sickness: Give full dose prophylactically 30 min before exposure to motion, and repeat before meals and at bedtime.
Nighttime sleep aid: 50 mg PO at bedtime.
Stay updated, free articles. Join our Telegram channel
Full access? Get Clinical Tree
