FDA Reviewing Safety of Botox After Deaths

Botox, Botox Cosmetic and Myobloc have been linked to severe adverse events, including respiratory failure and death, after being used for a variety of conditions, the FDA said. As a result, the agency is reviewing clinical trial safety data and postmarketing event reports for Allergan’s Botox and Botox Cosmetic (botulinum toxin type A) and Solstice Neurosciences’ Myobloc (botulinum toxin type B).

The adverse events may be related to overdosing and occurred after both FDA-approved and nonapproved uses. There is no evidence the reactions are related to a product defect, the agency said in an early communication.

The reported adverse reactions are similar to botulism, which occurs when botulinum toxins spread beyond the injection site. The symptoms include difficulty swallowing, weakness and breathing problems. The most severe adverse events occurred in children treated for limb spasticity associated with cerebral palsy, which is not an FDA-approved use. In fact, botulinum toxins have not been established as safe and effective for that condition or for any condition in children younger than 12.

Other serious adverse events occurred after treatment of a variety of conditions using a range of botulinum toxin doses. The effects were reported as early as one day and as late as several weeks following treatment.

The agency will announce its conclusions and recommendations after completing a review of clinical trial safety data, postmarketing adverse event reports and medical literature.