Retrospective survey to evaluate the safety and efficacy of Japanese botulinum antitoxin therapy in Japan

• A total of 134 patients administered botulinum antitoxins were detected in Japan.
• Side effects of antitoxins were reported in 2 patients, but both were not fatal.
• The fatality rate was 9.4% among 127 patients properly administered antitoxins.
• More than 70% of the patients showed improvement in their symptoms after treatment.

Japanese botulinum antitoxins have been used for more than 50 years; however, their safety and therapeutic efficacy are not clear. In order to analyze the available data on botulinum antitoxin therapy in Japan, we surveyed published reports about botulism cases in which botulinum antitoxins were used, and retrospectively analyzed the safety and efficacy of the therapy.A total of 134 patients administered botulinum antitoxins were identified from published reports. Two cases of side effects (1.5%) were detected after antitoxin administration, both not fatal. The fatality rate was 9.4%, and more than 70% of the patients showed improvement in their symptoms and better clinical conditions than those not treated with antitoxins. These data suggest that the therapy with Japanese antitoxins is safe and highly effective.