Botulinum toxin treatment of sialorrhea: comparing different therapeutic preparations.

In recent years, a number of potential new therapeutic indications of botulinum toxin injections have emerged, amongst which sialorrhea has attracted considerable attention. Based on open-label and controlled studies, botulinum toxin can be used to improve sialorrhea in patients with Parkinson's disease, parkinsonian syndromes, motor neuron disease and cerebral palsy. The toxin can be injected blindly based on anatomic landmarks of the salivary glands, or localization can be facilitated by use of ultrasound guidance. There are few reported adverse effects. However, many more carefully designed, controlled studies are still required to address the specific questions related to selection of patients, the optimal injection technique, the appropriate dose of botulinum toxin and its long-term effects.