Diphenhydramine
- Atc Codes:D04AA32#R06AA02
- CAS Codes:88637-37-0#58-73-1#147-24-0
- PHARMGKB ID:88637-37-0#58-73-1#147-24-0
Table of contents
- Brand Names
- Drug Combinations
- Chemistry
- Pharmacologic Category
- Mechanism of Action
- Therapeutic Use
- Pregnancy and Lactation Implications
- Contraindications
- Warnings and Precautions
- Adverse Reactions
- Caution and personalized dose adjustment in patients with the following genotypes
- Other genes that may be involved
- Substrate of
- Inhibits
- Drug Interactions
- Nutrition/Nutraceutical Interactions
- Dosage
- Pharmacokinetics and Pharmacodynamics
- Special Considerations
Brand Names
Europe
Austria: Calmaben, Dibondrin, Histaxin; Belgium: Azaron, Diphamine, Nustasium, R Calm; Bulgaria: Dermodrin, Psilo-Balsam; Cyprus: Belarmin, Histergan; Denmark: Benylan; France: Butix, Nautamine; Germany: Adedorm, Adiphen, Anaesthecomp, Ankadorm, Arbid S, Betadorm, Bodyguardpharm, Boxocalm, Bur-Dorm, CC-Nox, Diphenhydramin, Docpelin «Nachtsterne», Dolestan, Dorm-«Berco», Dormiagil, Dormicin N, Dormo-EBS, Dormocaps, Dormutil N, Dramadorm, Ehanox, Emesan, Halbmond, Hemodorm, Leodorm, Logomed Beruhigungs, Lunadorm, Lupovalin, Majodorm, Markodorm, Moradorm, Nervo Opt N, Noctiphen, Palmicol, Regudorm, Röwo-Dorm, S 8, Schlaf, Sedativum, Sedawaman, Sediat, Sedopretten, Sodormwell, Stawodorm, Stellaval, Urbadorm, Vivinox, Wolfsburger Schlaf; Greece: Benadryl, Diphenhydramine; Greece: Benadryl, Diphenhydramine; Hungary: Daedalon, Daedalonetta, Psilo-Balsam; Italy: Aliserin; Latvia: Pretniezes, Psilo-Balsam; Lithuania: Psilo-Balsam; Malta: Paxidorm, Nytol, Numark Night Time; Poland: Benzhydraminum, Dermodrim; Portugal: Benaderma, Benergina, Codilergi, Drenoflux; Romania: Calmaben, Dermodrin; Slovakia: Calmaben, Psilo-Balsam; Spain: Benadryl, Dormplus, Neosayomol, Sleepia, Soñodor; Sweden: Desentol; UK: Boots Sleepeaze, Nytol Original.
North America
Canada: Aller-Aide, Allerdryll, Allergy Elixir, Allergy Formula, Allernix, Benadryl, Calmex, Children’s Allergy Formula, Children’s Cough, Cold & Allergy Strips, Children’s Liquid Allergy Formula, Dimetane Allergy, Diphenhydramine, Diphenist, Dormax, Dormex, Dormiphen, Extra Strength Allergy, Insomnal, Jack & Jill Bedtime, Nadryl, Night Cough Liquid Fastgels, Nytol, Simply Sleep, Sleep Aid, Sleep-Eze, Sominex, Triaminic Thin Strips Nighttime Cough & Runny Nose, Unisom; USA: Benadryl, Diphenhydramine.
Latin America
Argentina: Amodormin, Difenhidramina, Fabolergic, Fadalex, Histaler, Klonadryl, Nelfigen, Theraflu Alergia; Brazil: Difenidrin; Mexico: Benadryl, Bionaryl, Bonanoti, Difenhidramina, Drafen, Glicodril, Histadryl, Indumir, Lurispan, Nytol, Ulcoid.
Asia
Japan: Diphenhydramine, Resmin, Restamin, Vena, Venasmin.
Drug combinations
Diphenhydramine and Acetaminophen
Diphenhydramine and Calamine
Diphenhydramine and Dextrometorphan
Diphenhydramine and Ibuprofen
Diphenhydramine and Naphazoline
Diphenhydramine and Pseudoephedrine
Diphenhydramine, Acetaminophen, and Ascorbic Acid (Vitamin C)
Diphenhydramine, Acetaminophen, and Pseudoephedrine
Diphenhydramine, Aloe Vera, and Calamine
Diphenhydramine, Ammonium Chloride, Codeine
Diphenhydramine, Hydrocortisone, and Neomycin
Diphenhydramine, Naphazoline, and Phenylephrine
Diphenhydramine, Antipyrine, Ephedrine and Nitrofurazone
Diphenhydramine, Bromhexine, Dextrometorphan, and Ephedrine
Diphenhydramine, Benzalkonium Chloride, Chlorhexidine, Hydrocortisone, and Salicylate
Diphenhydramine, Acetaminophen, Ascorbic Acid (Vitamin C), Caffeine, Codeine, and Phenylephrine
Chemistry
Diphenhydramine Citrate: C~17~H~21~NO C~6~H~8~O~7~. Mw: 447.48. (1) Ethanamine, 2-(diphenylmethoxy)-N,N-dimethyl-, 2-hydroxy-1,2,3-propanetricarboxylate (1:1); (2) 2-(Diphenylmethoxy)-N,N-dimethylethylamine citrate (1:1). CAS-88637-37-0; CAS-58-73-1 (diphenhydramine).
Diphenhydramine Hydrochloride: C~17~H~21~NO HCl. Mw: 291.82. Ethanamine, 2-(diphenylmethoxy)-N,N-dimethyl-, hydrochloride. CAS-147-24-0.
Pharmacologic Category
First Generation Antihistamines; Histamine H~1~ Antagonist. Anxiolytics, Sedatives, and Hypnotics; Miscellaneous. Antitussives. Skin and Mucous Membrane Agents; Antipruritics and Local Anesthetics. (ATC-Code: D04AA32; R06AA02).
Mechanism of action
Competes with histamine for H~1~-receptor sites on effector cells in the GI tract, blood vessels, and respiratory tract.
Therapeutic use
Allergic symptoms caused by histamine release including nasal allergies and allergic dermatosis. Adjunct to epinephrine in the treatment of anaphylaxis. Nighttime sleep aid. Prevention or treatment of motion sickness. Antitussive. Management of parkinsonian syndrome including drug-induced extrapyramidal symptoms. Topically for relief of pain and itching associated with insect bites, minor cuts and burns, or rashes due to poison ivy, poison oak, and poison sumac.
Pregnancy and lactiation implications
Teratogenic effects not observed in animal studies. Crosses the human placenta. Signs of toxicity and symptoms of withdrawal reported in infants following high doses or chronic maternal use close to term. The drug has been evaluated for the treatment of hyperemesis gravidarum. It is generally not considered the antihistamine of choice for treating allergic rhinitis or nausea and vomiting during pregnancy. Use while breast-feeding is contraindicated.
Unlabeled use
Contraindications
Hypersensitivity to diphenhydramine or any component of the formulation. Acute asthma. Neonates or premature infants. Breast-feeding. Use as a local anesthetic (injection).
Warnings and precautions
May cause CNS depression. Use with caution in history of asthma, cardiovascular disease, increased intraocular pressure or angle-closure glaucoma, prostatic hyperplasia and or GU obstruction, pyloroduodenal obstruction (including stenotic peptic ulcer) or thyroid dysfunction. Effects may be potentiated with other sedative drugs or ethanol. Caution in the elderly (more sensitive to adverse effects) and in children (may cause excitation). Some products may contain phenylalanine or soy protein (caution with allergies). Avoid concomitant use with other products containing diphenhydramine, even ones used on the skin. Topical products should not be used on large areas of the body, or on chickenpox or measles. Use of diphenhydramine as a sleep aid is discouraged due to its anticholinergic effects.