Abstract
Botulinum neurotoxin (BoNT) is considered the treatment of choice for various symptoms and diseases such as focal dystonia and focal spasticity. The effects of BoNT on the salivary glands have also been known for years, but their use was limited because of a lack of approval studies. Now the indication of sialorrhea is approved in some countries for incobotulinumtoxinA, such as the USA and Europe, and therapy could also become the treatment of choice. According to the pivotal study, a dose of 100 units of incobotulinumtoxinA, which is divided into the parotid and submandibular glands, is recommended. RimabotulinumtoxinB is approved in the USA only. To define the value of this therapy, we must consider anatomy, physiology, and available therapies. Therapy includes conservative measures such as functional dysphagia therapy, oral or transdermal application of anticholinergics, and, in selected cases, radiotherapy and surgical procedures. A combination of different approaches is optional. On the basis of the evidence and clinical experience, BoNT injections will be the first line of pharmacotherapy for chronic sialorrhea.