Methylphenidate is prescribed for hyperactive children with attention deficit disorder and in some cases of narcolepsy (uncontrollable tendency to fall asleep). Its adverse effects include neuropsychological and cardiovascular disorders, retarded growth in children, abuse and dependence.

Methylphenidate belongs to the family of amphetamines such as fenfluramine (formerly Ponderal°) and benfluorex (formerly Mediator° or other brands). Some of these drugs, used as appetite suppressants, were withdrawn from the market following the occurrence of pulmonary arterial hypertension and cardiac valve disease.

At Prescrire's request, the French and British medicines agencies provided data on adverse effects in patients taking methylphenidate. Pulmonary arterial hypertension occurred with the usual doses, sometimes clearing up when treatment was halted, and the drug possibly caused cardiac valve disease, including in children. The increased risk is probably low, but there are not sufficient epidemiological studies to evaluate it.

Informing patients and healthcare professionals crucially requires including this information on the methylphenidate patient leaflet. Symptoms suggestive of these adverse effects, such as difficulty in breathing in the absence of any physical effort, must be monitored. It is advisable not to use methylphenidate except in cases when hyperactivity or narcolepsy severely disrupt the patient's life. In such cases it is important to use the minimum effective dose.

©Prescrire 1 June 2015

"Methylphenidate: pulmonary hypertension and heart valve disease" Prescrire Int 2015; 24 (161): 154-155. (Pdf, subscribers only).