Trial of Diphenhydramine for Sleep in Children With Autism

Stanford University

Status and phase: Enrolling; Phase 2

Conditions: Autism Spectrum Disorder; Autism

Treatments: Drug: Placebo; Drug: Diphenhydramine

Study type: Interventional

Funder types: Other; NIH

Identifiers

NCT05501678

IRB-66941

1P50HD109861 (U.S. NIH Grant/Contract)

Details and patient eligibility

About

The purpose of this study is to examine the effect of diphenhydramine on sleep in children and adolescents with Autism Spectrum Disorder (ASD). Diphenhydramine is an anti-histaminergic agent with strong hypnotic properties. To accomplish this, the investigators will use a randomized double-blind placebo-controlled crossover 8-week study design to examine the effect of diphenhydramine on sleep physiology as assessed by polysomnography (PSG), actigraphy, circadian rhythm, and clinical measures.

Enrollment: 26 estimated patients

Sex: All

Ages: 8 to 17 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

Participants will meet the following

• Outpatients between 8 and 17 years of age at the time of consent
• Diagnostic and Statistical Manual, 5th edition (DSM-5) criteria for Autism Spectrum Disorder (ASD) on the basis of clinical evaluation, confirmed with the Autism Diagnostic Interview-Revised (ADI-R) and the Autism Diagnostic Observation Schedule, 2nd Ed (ADOS-2)
• Males and females
• Availability of polysomnography (PSG) or actigraphy data
• Sleep disturbances as assessed using Children's Sleep Habits Questionnaire (CSHQ) with a score of 41 or higher
• care provider who can reliably bring participant to clinic visits, provide trustworthy ratings, and interacts with participant on a regular basis
• stable medications for at least 2 weeks, with the exception of Prozac which is required to be stable for at least 4 weeks
• no planned changes in psychosocial and biomedical interventions during the trial
• willingness to provide additional saliva samples and participate in key study procedures (i.e.,safety measurements every visit, PSG at weeks 4 and 8, and wear the actigraphy watch for 2 weeks before the beginning of trial as well as during the 8 weeks of the trial).

Exclusion criteria

Participants will be excluded if one or more of the following is met

• active suicidal ideation or DSM-5 diagnosis of schizophrenia, schizoaffective disorder, or psychotic disorder
• active medical problems: migraine, asthma, seizure disorder, significant physical illness (e.g., anaphylaxis, serious liver, renal, or cardiac pathology)
• evidence of a genetic mutation known to cause autism or intellectual disability (e.g., Fragile X Syndrome), metabolic, or infectious etiology for the participant's autism on the basis of medical history, neurologic history, and available tests for inborn errors of metabolism and chromosomal analysis
• pregnant or sexually active females not using a reliable method of contraception (urinary tests for pregnancy will be employed in this study)
• individuals taking beta-blockers (local or systemic), benzodiazepines, antiepileptic medications, melatonin and antihistamines
• history of hypersensitivity to diphenhydramine
• history of severe side effects from diphenhydramine
• history of adequate trial of diphenhydramine
• current use of any medications known to interact with diphenhydramine such as medications inhibiting CYP2D6
• taking anticholinergic agents (e.g., trihexyphenidyl, thioridazine).

Trial design

Primary purpose: Basic Science

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: Quadruple Blind

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26 participants in 2 patient groups

Diphenhydramine, then Placebo

Experimental group

Description:

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:

Drug: Diphenhydramine

Drug: Placebo

Placebo, then Diphenhydramine

Experimental group

Description:

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.

Treatment:

Drug: Diphenhydramine

Drug: Placebo