Tehran University of Medical Sciences Iranian Journal of Psychiatry 1735-4587 7 2 2012 06 15 87 92 Mohammad Reza Mohammadi Psychiatry and Psychology Research Center,Tehran University of Medical Sciences, Tehran, Iran. Seyed Ali Mostafavi MSc Department of Nutrition and Biochemistry, School of Public Health, Tehran University of Medical Sciences, Poursina Ave., Qods St., Tehran, Iran Seyed Ali Keshavarz MSc Department of Nutrition and Biochemistry, School of Public Health, Tehran University of Medical Sciences, Poursina Ave., Qods Mohammad Reza Eshraghian Payam Hosseinzadeh Mohammad Javad Hosseinzadeh-Attar Seyed Mohammad Ali Kooshesh Maryam Chamari Shahin Akhondzadeh 2015 10 14 Objective: The aim of this study was to determine melatonin effects on sleep patterns, symptoms of hyperactivity and attention deficiency in children with attention-deficit hyperactivity disorder (ADHD). Methods: Children with age range of 7-12 years who had a combined form of ADHD were randomly divided in to 2 groups according to gender blocks. One group took melatonin (3 or 6mg) combined with methylphenidate (Ritalin) (1mg/kg), and the other group took placebo combined with methylphenidate (1mg/kg). ADHD rating scale and sleep patterns questionnaires were completed. Research hypotheses were assessed at the baseline, the second, fourth and eighth weeks after the treatment. Results: The mean sleep latency and total sleep disturbance scores were reduced in melatonin group, while the scores increased in the placebo group (p≥0.05). Data analysis, using ANOVA with repeated measures, did not show any statistically significant differences between the two groups in ADHD scores. Conclusion: Administration of melatonin along with methylphenidate can partially improve symptoms of sleep disturbance. However, it does not seem to reduce attention deficiency and hyperactivity behavior of children with ADHD. https://ijps.tums.ac.ir/index.php/ijps/article/view/207 https://ijps.tums.ac.ir/index.php/ijps/article/download/207/203