The botulinum toxin challenge in the management of drooling in Parkinson disease

Background. Botulinum toxin type A (BTX-A) has been proven effective in blocking cholinergic fibers, even in the salivary glands. Drooling is a frequent symptom in degenerative disorders. Objective. To assess the efficacy of BTX-A in relieving excessive drooling in Parkinson disease (PD) patients. Methods. Four patients (M/F: 3/1; mean age = 72 ± 9.4 years; mean disease duration = 4.7 ± 3.5 years) with reported hypersialorrea were enrolled. Each parotid gland was injected with 15 U of Botox in two diffent sites, avoiding masseter muscle toxin diffusion. Every patient underwent a clinical evaluation in order to exclude severe dysphagia. At baseline and 1 month after BTX-A treatment, the total amount of sciallorrea was measured using 5 dental rolls placed in the patient's mouth and retained for 5 min; the weight difference between the dry and wet rolls was analyzed. A questionnaire for severity and social impact of drooling was administered at baseline and at the follow-up visit. Results. All subjects showed an objective reduction of total amount of saliva production, with a mean decrease of 30%. Only 3/4 patients experience a subjective improvement in severity and social impact of drooling. In one patient, a slight and short-lasting worsening of swallowing function was reported. No other side effects were documented. Conclusions. BTX-A injection in parotid glands is a useful and safe tool in relieving excessive drooling in PD patients, with consequent amelioration of problems in social participation.