Adverse event reporting for botulinum toxin type A

A recent article published in the Journal of the American Academy of Dermatology reviewed adverse events regarding botulinum toxin type A (BTX-A) reported to the Food and Drug Administration between 1989 and 2003. Although postmarketing surveillance is a vital mechanism to ensure drug safety, the events reported in this paper must be considered in context to be appropriately interpreted. The majority of data was related to therapeutic rather than cosmetic use. The proportion of serious adverse events was 33-fold higher for therapeutic use and no deaths were reported after cosmetic use. The data were derived from a spontaneous reporting system and do not include assessments of causality between the BTX-A and purported adverse events. The report notes that over a third of these events were related to off-label use of BTX-A, a common practice in dermatology, yet no significant differences were reported in rates of adverse events between on-label and off-label use. The report reflects a favorable safety profile for cosmetic use of BTX-A, and if misinterpreted, could lead to unreasonable conclusions regarding a product considered to be highly safe and effective.