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Antihistamine

Diphenhydramine for Sleep in Children with Autism

Phase 2
Recruiting
Led By Antonio Y. Hardan, MD
Research Sponsored by Stanford University
Eligibility Criteria Checklist
Specific guidelines that determine who can or cannot participate in a clinical trial
Must have
Be younger than 18 years old
Timeline
Screening 3 weeks
Treatment Varies
Follow Up up to 5 years
Awards & highlights

Summary

This trial is testing if diphenhydramine can help children and teens with Autism Spectrum Disorder sleep better. Diphenhydramine is usually used for allergies but also makes people sleepy by blocking certain chemicals in the body. Diphenhydramine has been shown to be effective in reducing the time it takes to fall asleep and the number of times children wake up during the night.

Who is the study for?
This trial is for children and adolescents aged 8-17 with Autism Spectrum Disorder who have sleep disturbances. They must be outpatients with stable medications, not planning any treatment changes during the study, and able to provide saliva samples. Those with certain medical conditions or on conflicting medications cannot participate.
What is being tested?
The trial tests if Diphenhydramine improves sleep in kids with autism using a double-blind method where neither doctors nor participants know who gets the real medicine or placebo. It's an 8-week study comparing drug effects to a fake pill (placebo) using sleep tracking and safety checks.
What are the potential side effects?
Diphenhydramine may cause drowsiness, dry mouth, constipation, blurred vision, or dizziness. In some cases, it can lead to more serious side effects like heart palpitations or allergic reactions but these are less common.

Timeline

Screening ~ 3 weeks
Treatment ~ Varies
Follow Up ~up to 5 years
This trial's timeline: 3 weeks for screening, Varies for treatment, and up to 5 years for reporting.

Treatment Details

Trial Design

2Treatment groups
Experimental Treatment
Group I: Placebo, then DiphenhydramineExperimental Treatment2 Interventions
Participants will first receive Placebo (fake tablet) for a 4-week period. A 25 mg dose of matching Placebo will be given at bedtime for one week and then will increase to 50 mg if needed and if well tolerated. Participants will then receive Diphenhydramine for a 4-week period. A 25 mg dose of Diphenhydramine will be given at bedtime for one week and then will increase to 50 mg if needed and if well tolerated.
Group II: Diphenhydramine, then PlaceboExperimental Treatment2 Interventions
Participants will first receive Diphenhydramine for a 4-week period. A 25 mg dose of Diphenhydramine will be given at bedtime for one week and then will increase to 50 mg if needed and if well tolerated. Participants will then receive Placebo (fake tablet) for a 4-week period. A 25 mg dose of matching Placebo will be given at bedtime for one week and then will increase to 50 mg if needed and if well tolerated.
Treatment
First Studied
Drug Approval Stage
How many patients have taken this drug
Diphenhydramine
2002
Completed Phase 4
~1140
Placebo
1995
Completed Phase 3
~2670

Research Highlights

Information in this section is not a recommendation. We encourage patients to speak with their healthcare team when evaluating any treatment decision.
Mechanism Of Action
Side Effect Profile
Prior Approvals
Other Research
Common treatments for Autism Spectrum Disorder (ASD) that have anti-histaminergic properties, such as diphenhydramine, work by blocking histamine H1 receptors, leading to sedative effects that help manage sleep disturbances. Niaprazine, another H1-receptor antagonist, and cyproheptadine, which also has anticholinergic and antiserotonergic properties, are used similarly. These treatments are crucial for ASD patients as they address sleep and behavioral issues, improving overall quality of life and daily functioning.
Evaluation of drug interventions for the treatment of sleep disorders in children with autism spectrum disorders: a systematic review.Placebo-controlled pilot trial of mecamylamine for treatment of autism spectrum disorders.Niaprazine in the treatment of autistic disorder.

Find a Location

Who is running the clinical trial?

National Institutes of Health (NIH)NIH
2,789 Previous Clinical Trials
8,138,118 Total Patients Enrolled
21 Trials studying Autism Spectrum Disorder
2,470 Patients Enrolled for Autism Spectrum Disorder
Stanford UniversityLead Sponsor
2,458 Previous Clinical Trials
17,494,735 Total Patients Enrolled
36 Trials studying Autism Spectrum Disorder
3,811 Patients Enrolled for Autism Spectrum Disorder
Antonio Y. Hardan, MDPrincipal InvestigatorStanford University
9 Previous Clinical Trials
455 Total Patients Enrolled
8 Trials studying Autism Spectrum Disorder
407 Patients Enrolled for Autism Spectrum Disorder

Media Library

Diphenhydramine (Antihistamine) Clinical Trial Eligibility Overview. Trial Name: NCT05501678 — Phase 2
Autism Spectrum Disorder Research Study Groups: Diphenhydramine, then Placebo, Placebo, then Diphenhydramine
Autism Spectrum Disorder Clinical Trial 2023: Diphenhydramine Highlights & Side Effects. Trial Name: NCT05501678 — Phase 2
Diphenhydramine (Antihistamine) 2023 Treatment Timeline for Medical Study. Trial Name: NCT05501678 — Phase 2
~17 spots leftby Dec 2026