Benadryl

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Benadryl

 [ben´ah-dril]
trademark for preparations of diphenhydramine hydrochloride, an antihistamine.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

diphenhydramine hydrochloride

Aler-Cap, Aler-Dryl, Allerdryl (CA), AllerMax, Altaryl, Anti-Hist, Banophen, Benadryl, Benadryl Allergy, Benadryl Child Chesty Cough (UK), Benadryl Children's Allergy Fastmelt, Benadryl Dye-Free Allergy, Benadryl Itch Relief, Compoz Nighttime Sleep Aid, Dermamycin, Diphen, Diphenhist, Dytan, Genahist, Histapryn, Histergan (UK), Hydramine, Mandalyn Paedetriac (UK), Nightcalm, Nytol, PMS-Diphenhydramine (CA), Siladryl, Simply Sleep, Sleepeaze (UK), Sleepettes D, Sleepinal, Sominex, Theraflu Thin Strips Multisymptom, Triaminic Thin Strips Children's Cough and Runny Nose, Twilite, Unisom Maximum Strength SleepGels

Pharmacologic class: Ethanolamine derivative, nonselective histamine1-receptor antagonist

Therapeutic class: Antihistamine, antitussive, antiemetic, antivertigo agent, antidyskinetic

Pregnancy risk category B

Action

Interferes with histamine effects at histamine1-receptor sites; prevents but doesn't reverse histamine-mediated response. Also possesses CNS depressant and anticholinergic properties.

Availability

Capsules: 25 mg, 50 mg

Elixir: 12.5 mg/5 ml

Injection: 10 mg/ml, 50 mg/ml

Strips (orally disintegrating): 12.5 mg, 25 mg

Syrup: 12.5 mg/5 ml

Tablets: 25 mg, 50 mg

Tablets (chewable): 12.5 mg, 25 mg

Tablets (orally disintegrating): 12.5 mg

Indications and dosages

Allergy symptoms caused by histamine release (including anaphylaxis, seasonal and perennial allergic rhinitis, and allergic dermatoses); nausea; vertigo

Adults and children over age 12: 25 to 50 mg P.O. q 4 to 6 hours, or 10 to 50 mg I.V. or I.M. q 2 to 3 hours p.r.n. (Some patients may need up to 100 mg.) Don't exceed 400 mg/day.

Children ages 6 to 12: 12.5 to 25 mg P.O. q 4 to 6 hours, or 1.25 mg/kg (37.5 mg/m2) I.M. or I.V. q.i.d. Don't exceed 150 mg/day.

Children ages 2 to 5: 6.25 mg P.O. q 4 to 6 hours. Don't exceed 37.5 mg/day.

Cough

Adults: 25 mg P.O. q 4 hours p.r.n. Don't exceed 150 mg/day.

Children ages 6 to 12: 12.5 mg P.O. q 4 hours. Don't exceed 75 mg/day.

Children ages 2 to 5: 6.25 mg P.O. q 4 hours. Don't exceed 37.5 mg/24 hours.

Dyskinesia; Parkinson's disease

Adults: Initially, 25 mg P.O. t.i.d.; may be increased to a maximum of 50 mg q.i.d.

Mild nighttime sedation

Adults: 50 mg P.O. 20 to 30 minutes before bedtime

Dosage adjustment

• Elderly patients

Off-label uses

• Drug-induced extrapyramidal reactions

Contraindications

• Hypersensitivity to drug

• Alcohol intolerance

• Acute asthma attacks

• MAO inhibitor use within past 14 days

• Breastfeeding

• Neonates, premature infants

Precautions

Use cautiously in:

• severe hepatic disease, angle-closure glaucoma, seizure disorders, prostatic hypertrophy, cardiovascular disease, hyperthyroidism

• elderly patients

• pregnant patients (safety not established)

• children younger than age 2 (safety not established).

Administration

• For motion sickness, administer 30 minutes before activity.

• For I.V. use, check compatibility before mixing with other drugs.

• Inject I.M. dose deep into large muscle mass; rotate sites.

• Discontinue drug 4 days before allergy skin testing to avoid misleading results.

Don't give within 14 days of MAO inhibitors.

Adverse reactions

CNS: drowsiness, dizziness, headache, paradoxical stimulation (especially in children)

CV: hypotension, palpitations, tachycardia

EENT: blurred vision, tinnitus

GI: diarrhea, constipation, dry mouth

GU: dysuria, urinary frequency or retention

Skin: photosensitivity

Other: decreased appetite, pain at I.M. injection site

Interactions

Drug-drug. Antihistamines, opioids, sedative-hypnotics: additive CNS depression

Disopyramide, quinidine, tricyclic antidepressants: increased anticholinergic effects

MAO inhibitors: intensified and prolonged anticholinergic effects

Drug-diagnostic tests. Skin allergy tests: false-negative results

Hemoglobin, platelets: decreased values

Drug-herbs. Angel's trumpet, jimson weed, scopolia: increased anticholinergic effects

Chamomile, hops, kava, skullcap, valerian: increased CNS depression

Drug-behaviors. Alcohol use: increased CNS depression

Patient monitoring

• Monitor cardiovascular status, especially in patients with cardiovascular disease.

• Supervise patient during ambulation. Use side rails as necessary.

Patient teaching

• Advise patient to avoid alcohol and other depressants such as sedatives while taking drug.

• Caution patient to avoid driving and other hazardous activities until he knows how drug affects concentration and alertness.

• As appropriate, review all other significant adverse reactions and interactions, especially those related to the drugs, tests, herbs, and behaviors mentioned above.

McGraw-Hill Nurse's Drug Handbook, 7th Ed. Copyright © 2013 by The McGraw-Hill Companies, Inc. All rights reserved

Benadryl

(bĕn′ə-drĭl)
A trademark for the drug diphenhydramine hydrochloride.
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.

Benadryl

A proprietary antihistamine developed in the mid-1940s which, like other older sedating agents, has been associated with fatal RTAs/MVAs.
 
Adverse effects Drowsiness, heartburn, dizziness.
Segen's Medical Dictionary. © 2012 Farlex, Inc. All rights reserved.

Benadryl®

Diphenhydramine Allergy medicine An antihistamine which, like other older sedating agents, has been associated with fatal MVAs. See Antihistamine.
McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.

Benadryl

A brand name for DIPHENHYDRAMINE.
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005
References in periodicals archive ?
If diphenhydramine (Benedryl, etc.) was discovered today it would be considered a wonder drug.
Led by Upjohn Co.'s Cortaid and Parke-Davis' Benedryl, the category could find new players if the FDA hastens its pace on O-T-C conversions.
Warner-Lambert Co., Morris Plains, N.J., got in on the nasal spray market by introducing Benedryl nasal spray in June.
Also, many of the prescription and over-the-counter medications that you may be taking, such as diphenhydramine (Benedryl), aspirin, and any medication for sleep or mood can have potentially dangerous interactions with alcohol.
Today Claritan competes with Warner-Lambert Co.'s Benedryl and Wyeth's Alavert.
Among the top-selling products are Claritin, supplied by Schering-Plough HealthCare Products Inc.; Benedryl, manufactured by Warner-Lambert Co.; and Alavert, supplied by Wyeth.