Gabapentin as Add-on Therapy to Trihexyphenidyl in Children with Dyskinetic Cerebral Palsy: A Randomized, Controlled Trial.

OBJECTIVE: To compare the efficacy of gabapentin as add-on therapy to trihexyphenidyl in the treatment of children with dyskinetic cerebral palsy (CP).

METHODS: An open-labelled, randomized, controlled trial was conducted among children aged 3-9 y with dyskinetic CP [Gross Motor Functional Classification System (GMFCS) 4-5]. Participants were assigned into two groups: gabapentin with trihexyphenidyl (n = 30) and trihexyphenidyl alone (n = 30). Dyskinesia Impairment Scale (DIS), Dystonia Severity Assessment Plan (DSAP), and International Classification of Functioning, Disability, and Health-Children and Youth Version (ICF-CY) were measured at baseline, 4 and 12 wk.

RESULTS: There was significant reduction in baseline dystonia in both the groups (DIS: p < 0.001; DSAP: p = 0.007; ICF-CY: p < 0.001) but when data were compared between the groups, there was no significant difference in the severity of dystonia at 4 wk and at 12 wk (DIS: p = 0.09; DSAP: p = 0.49; ICF-CY: p = 0.25). Constipation was the commonest side effect observed in both the groups [3 (11.5%) vs. 4 (14.3%)].

CONCLUSION: Trihexyphenidyl alone is as effective as combination of gabapentin with trihexyphenidyl in decreasing the severity of dystonia at 12 wk. Hence, there is no added benefit of gabapentin as add-on therapy for dystonia among children with dyskinetic CP.

TRIAL REGISTRATION: CTRI/2019/04/018603.