Evidence for the effectiveness of botulinum toxin for sialorrhoea.

Sialorrhoea is a common symptom in many neurological disorders. Recently, botulinum toxin has been introduced as a treatment for sialorrhoea, and in this paper, we review the evidence for its effectiveness. The publications on the topic were searched and reviewed independently by two authors using the scale developed by the Therapeutics and Technology Assessment subcommittee for the American Academy of Neurology. All papers identified in our search fulfilled were evaluated, and classified into 1 of the 4 levels of evidence. According to this scheme, the effectiveness of botulinum toxin A in the treatment of sialorrhoea is considered established (level A). Botulinum toxin B is considered probably effective in the treatment of sialorrhoea (level B).