Botulinum toxin therapy improves masseter spasticity in Amyotrophic Lateral Sclerosis

Rev Neurol (Paris). 2020 Dec;176(10):870-873. doi: 10.1016/j.neurol.2020.04.022. Epub 2020 Jul 8.


Fifteen ALS patients, with troublesome symptoms linked to masseter spasticity, benefited from BoNT-A injections in each masseter. Based on the medical records of patients, the effect of the first injection was assessed one month later. We retrospectively collected information for 12 patients. Eight of them reported a beneficial effect after the injection for the following symptoms: trismus, tongue, lip and cheek biting, and jaw clonus. Five patients indicated that dental care was easier after injection. Our study showed that injections of BoNT-A unequivocally reduced masseter spasticity in ALS patients who subsequently enjoyed greater comfort in their daily living.

Keywords: Amyotrophic Lateral Sclerosis; Botulinum toxin; Masseter; Spasticity; Trismus.

MeSH terms

  • Amyotrophic Lateral Sclerosis*
  • Botulinum Toxins, Type A / therapeutic use
  • Humans
  • Injections, Intramuscular
  • Muscle Spasticity
  • Retrospective Studies


  • Botulinum Toxins, Type A