FDA Warns of Deaths Linked to Botox

The FDA on Monday announced it is investigating reports of children's deaths and severe side effects
 for others treated for a variety of conditions with the drug Botox and related products.

The agency said it was reviewing the safety of Allergan's Botox and Botox Cosmetic (botulinum toxin Type A) and Solstice Neurosciences' Myobloc (botulinum toxin Type B) after reports of the adverse reactions, which included respiratory failure. The adverse reactions may be due to overdosing, and there was no indication
 they were related to defects in the products, according to the FDA.

The agency is responding to a petition filed last month by watchdog group Public Citizen, in which it asked the FDA to place a black box warning—the strictest warning—on these products.

Most of the children cited by the FDA were being treated with botulinum toxin products to control limb spasms caused by cerebral palsy. The agency hasn't approved the use of the drugs for such treatment, officials
 added.

The reactions appeared to be related to the spread of the botulinum toxin to areas away from the site of injection, and mimic symptoms of botulism poisoning, which can include difficulty swallowing, weakness, and breathing problems.

Currently, the drugs' label warns against using these products in people with neuromuscular disorders,
Katz said.

FDA officials said Friday that they weren't advising health care professionals to stop prescribing these products. However, they are urging physicians and their patients to watch for signs of botulism poisoning.

The agency said it is reviewing the safety data from clinical trials submitted by the makers of the drugs. In addition, it is looking at "post-marketing adverse event reports" and any published studies.