Case series: amantadine open-label treatment of impulsive and aggressive behavior in hospitalized children with developmental disabilities.

OBJECTIVE: A growing body of literature implicates interactions between glutamatergic and neostriatal dopaminergic neurotransmitter systems in the development and expression of impulsivity, hyperactivity, and stereotypy. Amantadine hydrochloride, a drug used in young children for influenza prophylaxis, acts both as an indirect dopamine agonist as well as an N-methyl-D-aspartate (NMDA) receptor antagonist. Thus an open clinical trial of this medication for the treatment of symptoms of impulse control disorders in children was performed. METHOD: A total of eight children (seven with neurodevelopmental disorders and all inpatients) with target behaviors refractory to other treatments were selected after parental informed consent. All patients were male and ranged in age from 4 to 12 years. Outcome was based on subjective consensus clinical ratings by the multidisciplinary treatment team. RESULTS: For four of the children, amantadine was associated with marked clinical improvement. In the remainder, improvement was also observed. Amantadine was well tolerated. CONCLUSIONS: On the basis of this experience, it appears that amantadine hydrochloride or related NMDA antagonists may warrant additional study in this and related populations.