Attention deficit hyperactivity disorder (ADHD) is the most common behavioral disorder of childhood and it has 5% prevalence among children worldwide [1]. In the treatment of ADHD stimulant medications are recommended as the first choice of pharmacotherapy [2]. Methylphenidate-HCl is a sympathomimetic amine derivative pharmacological agent;and it is widely used in the treatment of ADHD. Although there are some articles showing that oral methylphenidate increases the risk of glaucoma [3], to the best of our knowledge, there is only one case report that indicates a possible relation of methylphenidate treatment and cataract formation [4].