Age-dependent effects of trihexyphenidyl in extrapyramidal cerebral palsy

Tribexyphenidyl (Artane) is a centrally active muscarinic antagonist common ly used to treat patients with generalized dystonia. In a retrospective sur vey of 22 consecutive children with extrapyramidal cerebral palsy, we evalu ated trihexyphenidyl on upper extremity and lower extremity function, expre ssive language, and drooling. Functional changes were assessed using a pare ntal questionnaire (rating scale 1-5: from 1 = little or no change to 5 = t remendous change, with scores in either a positive or negative direction). Improvements of +4 or +5 were reported in eight children for upper extremit y function, in eight children for verbal expressive language, in five for d rooling, and in none for lower extremity function. Using bivariate linear r egression modeling to investigate variables associated with treatment effec ts, there was a significant inverse relationship between age at initiation of medication and therapeutic response. Furthermore, beneficial responses w ere specific to upper-extremity function and expressive language. These res ults suggest that younger children are more likely to respond to trihexyphe nidyl and that primary functional benefits include improved fine motor abil ities and expressive language. A prospective masked study with a standardiz ed clinical instrument is needed to confirm these findings. (C) 2001 by Els evier Science Inc. All rights reserved.