Clinical use of amantadine in brain injury rehabilitation.

We retrospectively reviewed the charts of 12 subjects with brain injury who were treated with amantadine. Ten of the 12 subjects exhibited some improvement in cognitive and/or physical function while on amantadine. Areas most consistently showing improvement included focused and sustained attention and concentration, orientation, alertness, arousal, processing, time, and psychomotor speed, mobility, vocalization, agitation, anxiety and participation in therapy. Two of the three subjects with severe agitation showed dramatic resolution of the agitation. Eight of nine low-arousal subjects displayed an increased level of responsiveness. Areas with inconsistent response included memory, assaultiveness, and confusion. No response was seen in depression or sexual inappropriateness. Possible side-effects of amantadine were noted in five of the 12 subjects, and included pedal oedema, hypomania, generalized seizure, and visual hallucinations. This work suggests amantadine may play a role in neurobehavioural recovery of brain injury, and demonstrates the need for more in-depth study.