What side effects are associated with this type of intervention?

Diphenhydramine, an antihistamine with strong hypnotic properties, is commonly used to manage sleep disorders in children with Autism Spectrum Disorder (ASD). Known side effects of diphenhydramine include drowsiness, dizziness, dry mouth, constipation, blurred vision, and urinary retention. In some cases, it may cause paradoxical excitation, particularly in children, leading to increased activity and restlessness. Other sedative medications used in ASD, such as benzodiazepines, can have side effects like cognitive impairment, dependency, and paradoxical reactions such as increased agitation or aggression.

What prior FDA approvals exist?

The FDA has approved risperidone and aripiprazole for the treatment of irritability associated with Autism Spectrum Disorder (ASD). These medications are antipsychotics and are not directly similar to diphenhydramine, which is an anti-histaminergic agent with hypnotic properties. While diphenhydramine itself is not FDA-approved specifically for ASD, it has been studied for its effects on sleep in children with ASD due to its sedative properties. Other medications used off-label for sleep disturbances in ASD include melatonin and clonidine, which have different mechanisms of action but are used to address similar symptoms.

What other types of research exist?

Promising alternatives to Diphenhydramine for treating sleep disorders in Autism Spectrum Disorder patients include melatonin, clonidine, guanfacine, and trazodone. Melatonin is widely used for its safety and efficacy in managing sleep problems in children with neurodevelopmental disorders. Clonidine and guanfacine are alpha-2 adrenergic agonists that have shown benefits in reducing sleep disturbances. Trazodone, an antidepressant with sedative properties, is also considered for its effectiveness in improving sleep.

← Back to Search

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 baseline, week 1, week 2, week 3, week 4, week 5, week 6, week 7, and week 8

Awards & highlights

Study Summary

This trial will examine the effect of an anti-histamine on sleep in children & adolescents with ASD, using 8-week randomized double-blind placebo-controlled study design.

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.Check my eligibility

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.See study design

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 weeks3 visits

Treatment ~ Varies

Follow Up ~ baseline, week 1, week 2, week 3, week 4, week 5, week 6, week 7, and week 8

Screening ~ 3 weeks

Treatment ~ Varies

Follow Up ~baseline, week 1, week 2, week 3, week 4, week 5, week 6, week 7, and week 8

This trial's timeline: 3 weeks for screening, Varies for treatment, and baseline, week 1, week 2, week 3, week 4, week 5, week 6, week 7, and week 8 for reporting.

Treatment Details

Study Objectives

Outcome measures can provide a clearer picture of what you can expect from a treatment.

Primary outcome measures

Change from baseline in duration of non-rapid eye movement (NREM) sleep as measured by polysomnography (PSG)

Change from baseline in sleep latency as measured by polysomnography (PSG)

Secondary outcome measures

Change from baseline in sleep efficiency as measured by polysomnography (PSG) and actigraphy

Other outcome measures

Change from baseline on Aberrant Behavior Checklist, Second Edition (ABC-2) subscale scores

Change from baseline on Child Behavior Checklist (CBCL) scores

Change from baseline on Children's Sleep Habits Questionnaire (CSHQ) subscale scores

+8 more

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

Placebo

1995

Completed Phase 3

~2670

Diphenhydramine

2002

Completed Phase 4

~1170

Do I qualify?Apply below to find out

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

2,720 Previous Clinical Trials

7,494,453 Total Patients Enrolled

21 Trials studying Autism Spectrum Disorder

2,470 Patients Enrolled for Autism Spectrum Disorder

Stanford UniversityLead Sponsor

2,408 Previous Clinical Trials

17,343,381 Total Patients Enrolled

33 Trials studying Autism Spectrum Disorder

4,071 Patients Enrolled for Autism Spectrum Disorder

Antonio Y. Hardan, MDPrincipal InvestigatorStanford University

8 Previous Clinical Trials

425 Total Patients Enrolled

7 Trials studying Autism Spectrum Disorder

377 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

Unbiased ResultsWe believe in providing patients with all the options.

Your Data Stays Your DataWe only share your information with the clinical trials you're trying to access.

Verified Trials OnlyAll of our trials are run by licensed doctors, researchers, and healthcare companies.