Botulinum toxin effect on salivary flow rate in children with cerebral palsy

Objective: To investigate the effectiveness of botulinum neurotoxin (BoNT) type A in reducing salivary flow rate in children with cerebral palsy (CP) with severe drooling. Methods: During a controlled clinical trial, single-dose BoNT injections into the submandibular salivary glands were compared with scopolamine treatment. Forty-five school-aged children were included. Salivary flow rates from all major glands were obtained at baseline and compared with measurements during the interventions. Basic statistics consisted of analysis of difference scores. Results: Compared with baseline, the mean decrease in submandibular flow was 25% during scopolamine and 42% following BoNT injections. The difference scores were significant with maximum reductions 2, 4, and 8 weeks following BoNT. Of all children, 95% responded during scopolamine. Response rates for BoNT were significantly lower and varied from 69% at 2 weeks to 49% at 24 weeks after injection ( the end of the study). Four patients discontinued scopolamine therapy because of side effects. Only incidentally mild side effects were reported from BoNT. Conclusions: Intraglandular BoNT injections significantly reduce salivary flow rate in the majority of drooling CP children, demonstrating high response rates up to 24 weeks. The procedure is simple to perform, effective, and safe when ultrasound guidance is used. The anticholinergic effect of BoNT exceeds that of scopolamine. As anticholinergic drugs are frequently contraindicated because of side effects, BoNT injections offer an alternative in the treatment of drooling.