Methylphenidate (MPH) is frequently employed off-label and at high uncontrolled dosages, even beyond the scope of attention deficit hyperactivity disorder (ADHD) treatment. Intoxications appear to be infrequent and are documented in only a few case reports, with monitoring of plasma concentrations not consistently conducted. In the literature, there are no case reports or studies on the tolerability of high-normal doses of MPH.

Here we present a case of prolonged and excessive use of MPH without side effects before the patient was admitted to our psychiatric facility, following the consumption of illegal substances and a brief episode of acute confusion. Surprisingly, after admission, the patient's symptoms improved rapidly, before we substantially reduced the dose.