Systemic toxicity of botulinum toxin by intramuscular injection in the monkey

Botulinum toxin (Oculinum) was injected intramuscularly into eight monkeys. The LD50 dose is estimated to be approximately 39 U/kg body weight. The lowest dose that caused systemic toxicity, 33 U/kg, was close to the fatal dose range, 38-42 U/kg.