Melatonin Effects in Methylphenidate Treated Children with Attention Deficit Hyperactivity Disorder: A Randomized Double Blind Clinical Trial

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.