Thank you for your response Miyuru! Was methylphenidate discontinued in such cases or was there too little evidence to indicate that the drug caused the increase in impulsive aggression? My research lab found causal evidence of supra-optimal doses of MPH increasing impulsive responding in a task of selective attention (i.e. 3 times the dose that restored inattention from a developmental insult), but I have been unable to find any evidence that corroborates our observation.

Dear Stephane,

It is my personal clinical experience that in some the patients Methylphenidate increases impulsivity, aggression, lifts mood significantly.

It is dose dependent in some cases and not so in some cases. So I thought it depends on/differs from patient to patient. Clinically I cannot anticipate before hand which patient is going to show hyper-sensitivity and at what dose that patient would show hypersensitivity.

In some cases I was compelled to withdraw Methylphenidagte completely.

So many clinicians handle this medicine with care. But I prescribe it fearlessly to deserving patients.

Some researcher need to find out if any genetic or metabolic or some such physiological cause is responsible to such responses from some special patients only.

Withdrawal of medicine helps patient maintain mood/aggression.

Hope my response help you in some way. Wishing you all the very best.

Continue this discussion to draw more responses to add in our information.

Thanks.