Is myasthenia gravis a contraindication for botulinum toxin?

Botulinum toxin (BTX) is a neurotoxin that has been used to treat various disorders and has also become a popular choice for cosmetic indications, yet traditionally, myasthenia gravis (MG) is considered a contraindication for BTX. To determine whether BTX should be avoided in MG patients, clinical data from our MG and dystonia specialist clinic were analyzed retrospectively. In addition, a systematic literature review was conducted to identify all published cases associated with the co-existence of MG and BTX treatments. Here, we described one patient from our clinic, who received BTX injections before being given MG diagnosis. After the literature review, 8 cases with subclinical MG previously treated with BTX for dystonia or cosmetic reasons (BTX injections before MG diagnosis) were identified. Markedly, 8 out of 8 (100%) patients developed obvious muscle weakness. In contrast, 10 patients presenting MG as comorbidity had received BTX for dystonia or overactive bladder (BTX injection after MG diagnosis), and 8 out of 10 (80%) experienced improved symptoms through appropriate dose modifications and adequate treatment for MG before receiving BTX injections. These findings support that, under proper management of co-existing MG, BTX could be used safely and successfully in patients presenting MG comorbidities in the future. (C) 2021 Elsevier Ltd. All rights reserved.

Automated summary

Based on clinical data and literature review, it was found that under proper management, patients with myasthenia gravis (MG) can safely and successfully use botulinum toxin (BTX) for comorbidities.