Age-dependent effects of trihexyphenidyl in extrapyramidal cerebral palsy

Hoon, Alexander H; Freese, Patricia O; Reinhardt, Elsie M; Wilson, Mary Ann; Lawrie, William T; Harryman, Susan E; Pidcock, Frank S; Johnston, Michael V

« Previous Next »Pediatric Neurology
Volume 25, Issue 1 , Pages 55-58, July 2001

Age-dependent effects of trihexyphenidyl in extrapyramidal cerebral palsy

Alexander H Hoon Jr, MD, MPH
- Department of Pediatrics; Johns Hopkins University School of Medicine; Baltimore, MD, USA
- Kennedy Krieger Institute; Baltimore, MD, USA
- Communications should be addressed to: Dr. Hoon; Kennedy Krieger Institute and Johns Hopkins Medical Institutions; 707 North Broadway; Baltimore, MD 21205
Patricia O Freese, MS, PT
- Kennedy Krieger Institute; Baltimore, MD, USA
Elsie M Reinhardt, MSN, PNP
- Kennedy Krieger Institute; Baltimore, MD, USA
Mary Ann Wilson, PhD
- Department of Neurology; Johns Hopkins University School of Medicine; Baltimore, MD, USA
- Kennedy Krieger Institute; Baltimore, MD, USA
William T Lawrie Jr, AB
- Department of Physical Medicine and Rehabilitation; Johns Hopkins University School of Medicine; Baltimore, MD, USA
Susan E Harryman, MS, PT
- Kennedy Krieger Institute; Baltimore, MD, USA
Frank S Pidcock, MD
- Department of Physical Medicine and Rehabilitation; Johns Hopkins University School of Medicine; Baltimore, MD, USA
- Kennedy Krieger Institute; Baltimore, MD, USA
Michael V Johnston, MD
- Department of Pediatrics; Johns Hopkins University School of Medicine; Baltimore, MD, USA
- Department of Neurology; Johns Hopkins University School of Medicine; Baltimore, MD, USA
- Kennedy Krieger Institute; Baltimore, MD, USA

Received 23 October 2000; accepted 16 April 2001.

Abstract

Trihexyphenidyl (Artane) is a centrally active muscarinic antagonist commonly used to treat patients with generalized dystonia. In a retrospective survey of 22 consecutive children with extrapyramidal cerebral palsy, we evaluated trihexyphenidyl on upper extremity and lower extremity function, expressive language, and drooling. Functional changes were assessed using a parental questionnaire (rating scale 1–5: from 1 = little or no change to 5 = tremendous change, with scores in either a positive or negative direction). Improvements of +4 or +5 were reported in eight children for upper extremity function, in eight children for verbal expressive language, in five for drooling, and in none for lower extremity function. Using bivariate linear regression modeling to investigate variables associated with treatment effects, there was a significant inverse relationship between age at initiation of medication and therapeutic response. Furthermore, beneficial responses were specific to upper-extremity function and expressive language. These results suggest that younger children are more likely to respond to trihexyphenidyl and that primary functional benefits include improved fine motor abilities and expressive language. A prospective masked study with a standardized clinical instrument is needed to confirm these findings.