Iatrogenic botulism after botulinum toxin type A injections.

Therapeutic use of botulinum toxin type A (BT/A) is well known, effective, and safe. Iatrogenic botulism that presents with generalized weakness, dysphagia, and respiratory distress is a rare but significant complication in BT/A treatment. In this study, we report 4 patients who developed iatrogenic botulism after receiving therapeutic doses of BT/A for spasticity and blepharospasm. One patient was placed in intensive care unit, but consequently, every patient recovered fully. The cause of BT/A as an adverse effect is most likely hematological spread of the toxin.