A serious adverse event appeared to occur in approximately 1 in 100 children taking the stimulant methylphenidate, resulting in discontinuation of the treatment, according to the findings of a study published in the Cochrane Database of Systematic Reviews.
Methylphenidate is the most commonly prescribed drug to treat attention-deficit/hyperactivity disorder and has been in use for more than 50 years.
For their investigation, the authors identified 260 studies, including comparative and noncomparative cohort studies, patient-controlled studies, cross-sectional studies, methylphenidate arms from randomized clinical trials, and patient reports. The studies included children aged 3 to 20 years, each with a mean participant age ≤18 and a population where at least 75% of participants had IQ scores >70, which was required for inclusion.
Discontinuation of methylphenidate occurred in 7.3% of patients overall, with 1.2% experiencing a major adverse event, psychotic disorder, or arrhythmia. The remaining 6.2% withdrew following milder adverse events, including difficulty falling asleep, headache, abdominal pain, and decreased appetite. In comparative studies, the risk ratio for a serious adverse event was 1.36 (95% CI, 1.17-1.57).
The authors warned that it was not possible to estimate the precise actual risk for adverse events and that the risk may be higher than their findings suggested. They also found that most studies included were at critical risk for bias, according to the Grading of Recommendations Assessment, Development, and Evaluation system.
“Just as we need to be able to identify who is likely to benefit from treatment,” the authors stated, “we also need to be able to identify those who are most at risk of experiencing adverse events.”
Storebø OJ, Pedersen N, Ramstad E, et al. Methylphenidate for attention deficit hyperactivity disorder (ADHD) in children and adolescents – assessment of adverse events in non-randomised studies. Cochrane Database Syst Rev. 2018;5:CD012069.