PlainPill

Diphenhydramine

People mainly take Diphenhydramine for sleep. Based on 9 first-hand reports and 57 meta-analyses & systematic reviews in the medical literature. Ranked #778 of 1,974 overall.

21
User score
Mostly negative
0% positive33% mixed44% negative22% unclear

Of reports that state an outcome, 0% are positive.

Clinical research
AStrong research base
57
meta-analyses
298
RCTs
4,595
papers

What Diphenhydramine does, according to users

Of the people who reported each effect, the share who said it got better.

2 more with fewer than 3 reports
betterno changeworse

What the research says

Systematic reviews and meta-analyses from PubMed, with their published conclusions.

AStrong research base

3+ meta-analyses or systematic reviews and 10+ randomized controlled trials in humans. The grade measures how much human research exists — read the conclusions below for what it found.

Mol Psychiatry · 2023 · Meta-analysis / systematic review
Pharmacological interventions for antipsychotic-related sialorrhea: a systematic review and network meta-analysis of randomized trials

Conclusion: Considering primary nodes' co-primary efficacy outcomes and head-to-head comparisons, efficacy for sialorrhea is most consistent for the following agents, decreasing from metoclopramide through cyproheptadine, sulpiride, propantheline, diphenhydramine, benzhexol, doxepin, amisulpride, chlorpheniramine, to amitriptyline, and atropine (the latter not for nocturnal sialorrhea). Shared decision-making with the patient should guide treatment decisions regarding clozapine-related sialorrhea.

PubMed 37821573 ↗
J Eur Acad Dermatol Venereol · 2024 · Meta-analysis / systematic review
Treatment of acute urticaria: A systematic review

Conclusion: The addition of corticosteroids to an antihistamine as treatment for AU needs to be further investigated. Well-designed, high-quality interventional trials are needed to establish evidence-based treatment guidelines for AU.

PubMed 38420865 ↗
Clin Oral Investig · 2023 · Meta-analysis / systematic review
Supportive care and antiviral treatments in primary herpetic gingivostomatitis: a systematic review

Conclusion: Although PHGS is a disease with a high worldwide prevalence, the lack of consensus about therapeutic management indicates gaps in existing evidence. Most of the proposed treatment consists in symptomatic drugs with empiric regimens which are ineffective for the viral replication. The main limit to realize randomized clinical trial is due to the rapid onset and remission of the disease. In fact, the diagnostic delay, estimated in 72 h, decreases the effectiveness of any antiviral drugs.

PubMed 37733027 ↗
Hum Psychopharmacol · 2023 · Meta-analysis / systematic review
Efficacy and safety of hydroxyzine for sleep in adults: Systematic review

Conclusion: The studies in this review suggest hydroxyzine could be considered as a short-term treatment option for adults with insomnia for whom previous therapy was ineffective, not tolerated, or contraindicated. Additional long-term studies with an active comparator are needed to further establish its role in insomnia treatment.

PubMed 36843057 ↗

Dosage people report

As stated by users — not a recommendation. Follow the label or your doctor.

50 mgdaily
50 mgas reported
300 mgdaily

Reported side effects

How often each side effect came up across all reports.

drowsiness ×2brain fog ×1psychomotor impairment ×1seizures ×1mania ×1psychosis ×1reduced sleep ×1cardiac discomfort ×1

What users say

Verbatim quotes, shortened only — each links to the original discussion.

“I took benadryl for 3 years straight (50 mg) standard dose to help sleep.”
Source discussion ↗
“I've recently taken Benadryl and a doctor once prescribed me prescription antihistamine - hydroxyzine. These definitely knock me out, but I wake up very groggy”
Source discussion ↗
“if you’re desperate, give Sominex a go. Knocks me out and you wake up with no hang over”
Source discussion ↗
“After further testing, the substance was identified as diphenhydramine (Benadryl).”
Source discussion ↗
“diphenhydramine is terrible in the long run for cognition though.”
Source discussion ↗
Top discussions (5)

Other options for sleep

User data from public discussions; research from PubMed. Information only, not medical advice — talk to a doctor before starting, stopping or combining anything. Data updated October 2, 2026. How we rate