Treatment of sialorrhoea in patients with Parkinson's disease: best current evidence.

(1) Sialorrhoea is a common condition in patients with Parkinson's disease that has a negative impact on patient quality of life. (2) Traditionally, muscarinic antagonists have been the pharmacological agents of choice for the treatment of sialorrhoea; however, these agents are frequently associated with adverse events in patients with Parkinsonian disorders. (3) Recent studies suggest that botulinum toxin injection is currently the most effective treatment option for Parkinsonian-related sialorrhoea.