Objectives: The objective of this study was to analyze the safety and efficacy of botulinum toxin (BTX) therapy in a series of 1,000 treatments on 261 consecutive patients at the University Department of Otorhinolaryngology-Head and Neck Surgery, Cologne, Germany.
Study design/methods: A prospective computer database was analyzed, and all patient charts were reviewed retrospectively. In doing so, the main focus was put on patient characteristics, treatment methods, efficacy, unwanted side effects, and reinjection rate.
Results: A total of 16 different indications were treated with BTX belonging to the categories of focal dystonias, focal hyperhidrotic syndromes, and cosmetic dermatology. The overall morbidity was 1.3%, exclusively consisting of minor side effects. These were all reversible and mostly caused by paralysis of adjacent musculature. We did not observe any severe complications. Three (1.2%) patients developed a secondary nonresponse to BTX type A (BTX-A). Their treatment was continued with BTX type B. In 2.8% of treatments, patients thought the clinical effect was weak and returned for reinjection within 4 weeks after the first treatment.
Conclusion: The experience from the largest patient series known confirms that BTX-A injections are the therapy of choice for many forms of focal hyperhidrotic syndromes, focal dystonia, and hyperfunctional lines. It is an effective and safe treatment with only minor side effects. For optimal individual results, a thorough documentation of each treatment is necessary. Dosages should be as low as possible to reduce the probability of a patient developing a secondary nonresponse.