Attention deficit hyperactivity disorder (ADHD) is one of the most common neurodevelopmental disorders. It was once thought to be a disorder affecting only children, but in those undiagnosed in childhood, symptoms do not disappear with age. There is now a growing recognition of the late diagnosis and treatment of adults with ADHD. The first-line drug in pharmacotherapy is methylphenidate, and information about its adverse effects, when used by adults, has not been as extensively described as in children. The aim of this article was to review the literature describing the risks of methylphenidate therapy for adults with ADHD. A total of 19 articles-15 clinical trials and 4 case reports presenting rare side effects resulting from methylphenidate therapy, such as reversible ischemic stroke, myocardial infarction, and psychotic episodes, were analyzed. The analysis from clinical trials included 3458 adult patients with ADHD and described the most common side effects, psychiatric adverse events, effects of methylphenidate treatment on sleep, laboratory results, body mass, and cardiovascular symptoms. Methylphenidate treatment is well tolerated, with side effects described, according to severity, as mild to moderate. We conclude that pharmacotherapy is not risk-free and methylphenidate, due to its side effects, may not be the first drug of choice for every patient.
Keywords: ADHD; adults; adverse effects; methylphenidate; neurodevelopmental disorders; psychostimulants; serious adverse events; treatment risk.