IRCT20090117001556N124.

Study name	Cilostazol as adjunctive treatment of autism: a double blind and placebo controlled trial in children 5 to 11 years old
Methods	10‐week parallel trial of cilostazol versus placebo
Participants	Inclusion criteria: aged 5‐11 DSM‐V diagnosis of autism minimum ABC‐I score of 12 Exclusion criteria: any psychiatric disorder history of allergies to cilostazol or risperidone any medical conditions such as seizure disorders or heart conditions receipt of psychotropic medicines in the 2 weeks prior to the study
Interventions	Intervention (cilostazol + risperidone): 100 mg cilostazol morning and night plus risperidone 1‐3 mg/day Comparator (placebo + risperidone): 1‐3 mg/day of risperidone plus placebo
Outcomes	Primary outcomes: irritability, measured using the ABC‐I (Aman 1985) Secondary outcomes: unclear Timing of outcome assessments: baseline, week 5 and 10 (endpoint)
Starting date	30 May 2020
Contact information	Contact name: S. Akhondzadeh E‐mail: s.akhond@sina.tums.ac.ir
Notes	Source of funding: Tehran University of Medical Sciences Conflicts of interest: not reported