Myospasm and Fasciculation After Botulinum Toxin Injection.

Botulinum toxin type A (BTA) is commonly used to treat dystonia; however, reports of dystonia caused by BTA are rare. In this case study, the authors aimed to illustrate the instances of dystonia after cosmetic injections of BTA. Three cases were retrospectively analyzed, with follow-up evaluations conducted to assess the development and resolution of symptoms. Injection techniques, including microdroplet and intradermal methods, were examined, and potential hypotheses regarding the etiology of dystonia were explored. Recommendations for mitigating adverse effects were formulated based on the analysis of injection practices, including modifications to dosage, injection-site distribution, and volume. In all cases, patients experienced transient dystonia following BTA injections, with symptoms including muscle spasms and abnormal muscle contractions, which resolved spontaneously or with minor interventions. The findings suggest that the use of microdroplet techniques and careful injection strategies can minimize the risk of such adverse effects. In conclusion, the authors suggest that neurological injury, neuromuscular junction impact, uneven drug distribution, and imbalance between denervation and functional recovery may cause dystonia.