Botulinum neurotoxin (BoNT) is a second-line treatment of sialorrhoea in ALS (amyotrophic lateral sclerosis) patients. This article is a review of the published literature concerning safety and administration of this treatment to ALS patients. A PubMed search was performed. All original publications on BoNT treatment of sialorrhoea in ALS patients were included in the review. Only a few adverse events were observed concerning treatment with BoNT. The studies performed to date have applied different treatment strategies with different dosages. In conclusion, BoNT treatment for sialorrhoea in ALS patients is safe with few adverse effects. The authors advocate for the implementation of a personalized treatment strategy. Special precautions must be taken when patients do not have the assistance of a ventilator and a feeding tube.