Resveratrol adjunct to methylphenidate improves symptoms of attention-deficit/hyperactivity disorder: a randomized, double-blinded, placebo-controlled clinical trial.

ABSTRACT

Current pharmacological approaches have failed to provide complete remission for patients with Attention-Deficit/Hyperactivity Disorder (ADHD). This study aimed to evaluate the efficacy and tolerability of resveratrol (that have been shown to have antioxidative, anti-inflammatory, and anti-apoptotic effects) as an adjunct to methylphenidate in pharmacologic treatment of ADHD. This 8-week, double-blinded, placebo-controlled trial randomized 66 participants to receive either 500 mg/day resveratrol or matched placebo in addition to methylphenidate. ADHD symptoms were evaluated in the patients using the Parent and Teacher versions of ADHD-Rating Scale (ADHD-RS) at three measurement points with time intervals of 4 weeks. Furthermore, the tolerability of the treatment strategies was systematically compared. Repeated measures analysis demonstrated a significant effect for time-treatment interaction on all three subscales of the Parent ADHD-RS during the trial period (total p = 0.015; inattention p = 0.032; hyperactivity/impulsivity p = 0.036). Nevertheless, the effect for time-treatment interaction was not significant for the Teacher version of ADHD-RS (total F = 0.81, df = 1.33, p = 0.401; inattention F = 0.57, df = 1.37, p = 0.507; hyperactivity/impulsivity F = 0.65, df = 1.34, p = 0.466). The frequencies of complications in the treatment groups were similar. Resveratrol administration for a duration of 8 weeks improved characteristic symptoms in patients with ADHD according to their parents. Further investigations containing larger sample sizes, longer supplementation periods, and dose-response evaluations are required to replicate these findings in ADHD children more confidently.