Methylphenidate remains the first choice treatment for attention deficit hyperactivity disorder (ADHD), but comorbid forms with Disruptive Behaviour Disorders (DBD) are undertreated.

Methylphenidate adjunction is sometimes necessary in order to treat ADHD-related symptoms in DBD behaviors initially well-regulated with risperidone. In these situations, psychostimulant-antipsychotic combinations can be a useful strategy.

We report three cases of methylphenidate-risperidone combination in the context of our clinical experience with this bitherapy.

The cases show potential benefits to treat comorbid-ADHD with DBD with the psychostimulant-antipsychotic combination and the limits due to the risk of dyskinesia.