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Diphenhydramine Hcl

Also sold as Childrens Allergy Relief, Allergy Relief, Nighttime Sleep Aid, basic care nighttime sleep aid

From 4 official FDA drug labels · RxNorm 1020477

This comes from U.S. FDA labels. Brand names, strengths and advice can differ in your country; check with a local health professional. Set your country.

What it is used for

These are the uses the FDA has approved for this label. Using it for anything else is “off-label”: ask your prescriber why.

Use for relief of occasional sleeplessness.

How to take it

Directions adults and children 12 years of age and over: 1 softgel (50 mg) at bedtime if needed, or as directed by a doctor

Do not take it if

Do not use for children under 12 years of age with any other product containing diphenhydramine, even one used on skin

Ask a doctor or pharmacist before using it if

Ask a doctor before use if you have a breathing problem such as emphysema or chronic bronchitis glaucoma trouble urinating due to an enlarged prostate gland

Serious warnings and precautions

Warnings Do not use for children under 12 years of age with any other product containing diphenhydramine, even one used on skin Ask a doctor before use if you have a breathing problem such as emphysema or chronic bronchitis glaucoma trouble urinating due to an enlarged prostate gland Ask a doctor or pharmacist before use if you are taking sedatives or tranquilizers. When using this product avoid alcoholic drinks. Stop use and ask a doctor if sleeplessness persists continuously for more than 2 weeks. Insomnia may be a symptom of a serious underlying medical illness. If pregnant or breast-feeding, ask a health professional before use. Keep out of reach of children. In case of overdose, get medical help or contact a Poison Control Center (1-800-222-1222) right away.

When using this product

When using this product avoid alcoholic drinks.

Stop using it and ask a doctor if

Stop use and ask a doctor if sleeplessness persists continuously for more than 2 weeks. Insomnia may be a symptom of a serious underlying medical illness.

If you are pregnant or breastfeeding

If pregnant or breast-feeding, ask a health professional before use.

Keep out of reach of children

Keep out of reach of children. In case of overdose, get medical help or contact a Poison Control Center (1-800-222-1222) right away.

Forms and strengths available

38 MG / 200 MG · Oral Tablet25 MG / 200 MG · Oral Capsule50 MG · Oral Capsule25 MG · Oral Tablet50 MG/ML · Injectable Solution0.02 MG · Topical Gel1.25 MG/ML · Oral Solution10 MG/ML · Topical Cream12.5 MG · Chewable Tablet2.5 MG/ML · Oral Solution25 MG · Oral Capsule20 MG/ML · Topical Cream25 MG / 10 MG · Oral Tablet50 MG · Oral Tablet2.5 MG/ML / 1 MG/ML · Oral Solution20 MG/ML / 1 MG/ML · Topical Cream25 MG · Disintegrating Oral Tablet0.02 MG / 0.01 MG · Topical Gel1.25 MG/ML / 0.5 MG/ML · Oral Solution20 MG/ML / 10 MG/ML · Topical Cream1.67 MG/ML · Oral Solution0.5 MG/ML · Injectable Solution1 MG/ML · Injectable Solution2 MG/ML · Oral Solution

From RxNorm. Which forms and strengths are actually stocked varies by pharmacy and country.

Reactions people have reported

disease progression 10dizziness 2flushing 1international normalised ratio increased 1hypersomnia 1oesophageal candidiasis 1acute myocardial infarction 1unevaluable event 1blood pressure diastolic decreased 1haemoglobin decreased 1

These are counts from 16 voluntary reports to the FDA. They show what has been reported — they are not how common a side effect is, and they do not prove the medicine caused it.

Recalls

Class II · Jun 15, 2022
Diphenhydramine HCl oral solution, USP, 25 mg/10 mL UD, packaged in a) 10 mL unit dose cups (NDC 0121-0978-10), b) 100-count box (NDC 0121-0978-00), Rx only, MFG: Pharmaceutical Associates Inc.
Reason: cGMP deviations: Temperature abuse
Class II · Jun 2, 2021
Banophen Diphenhydramine HCl 25 mg Antihistamine 100 capsules NDC 0904-5306-60 Distributed by: Major Pharmaceuticals 31778 Enterprise Drive Livonia, MI 48150 USA
Reason: CGMP Deviations: Intermittent exposure to temperature excursion during storage.
Class II · Aug 7, 2019
Equate Night-time Sleep Aide (Diphenhydramine HCl), 50 mg, Alcohol Free, Berry Flavor, 12 Fl. Oz. (354 mL), OTC, Distributed by: Walmart Stores, Inc., Bentonville, AR 72716, NDC 49035-330-02, UPC 6 8113117595 1
Reason: Microbial contamination of non-sterile product
Class III · Mar 26, 2014
Advil PM Caplets, (Ibuprofen, 200 mg /Diphenhydramine citrate, 38 mg) 120 count bottle, OTC, Pfizer, Madison, NJ 07940 USA. NDC 0573-0164-43
Reason: Subpotent Drug: This lot is being recalled because of out-of-specification test results for Diphenhydramine citrate.

Research & studies

Recent higher-quality studies about Diphenhydramine Hcl, from PubMed. We link to the source — titles only. This is not medical advice.

ReviewPharmacology of Commonly Used Sedative Agents.Dental clinics of North America · 2026 OctReviewComparative Efficacy of Interventions for the Prevention and Treatment of Postpartum Depression: A Bayesian Network Meta-analysis.Clinical psychopharmacology and neuroscience : the official scientific journal of the Korean College of Neuropsychopharmacology · 2026 Aug 31ReviewCloperastine in paediatric and adult cough management: a historical narrative review.Drugs in context · 2026Randomized Controlled TrialImpact of IV metoclopramide + diphenhydramine on post-concussion symptoms. A secondary analysis of data from an ED-based randomized study.Headache · 2026 SepRandomized Controlled TrialPsilocybin in the Treatment of Cocaine Use Disorder: A Randomized Clinical Trial.JAMA network open · 2026 May 1Systematic ReviewEfficacy and outcomes of pharmacological treatments for headaches after traumatic brain injury: A systematic review.Cephalalgia : an international journal of headache · 2026 Apr

Similar medicines

Diphenhydramine Hcl belongs to the Propionic acid derivatives class. Other medicines in it:

ibuprofenesomeprazolenaproxen

Questions to ask your doctor or pharmacist

Why you can trust this

Everything above comes from official FDA drug labels (openFDA), not written by us. Here are the exact labels used.

This information explains the official label. It cannot tell you whether this medicine is right or safe for you personally — only a qualified health professional who knows your history can do that. Do not start, stop, or change a medicine based on this page alone.