Botox Side Effects Lead to FDA Mandated Black Box Warning

The FDA is requiring that a “black box” warning be placed on Botox and other botulinum toxin products, such as Botox Cosmetic, Myobloc and Dysport, due to a potential risk of life-threatening side effects that may occur if the toxin spreads to other areas of the body.

Botox and the other products contain small quantities of Botulinum Toxin A, which is the bacteria associated with the development of botulism poisoning, a condition which causes the muscles to become paralyzed.

The injections are approved for cosmetic uses to help reduce the occurrence of wrinkles, as well as to treat conditions like crossed eyes, excess sweating, involuntary contractions of the neck muscles and involuntary blinking of the eye. It is also widely used off-label to treat conditions like muscle spasticity associated with cerebral palsy.

The FDA has received a number of reports involving problems caused by Botox side effects, including reports of hospitalizations and deaths. Most of the serious issues have been associated with off-label Botox treatment of cerebral palsy in children. However, there have also been reports of adverse reactions among adults receiving the medication for both approved and off-label uses.

According to a statement released by the FDA on April 30, 2009, manufacturers will be required to add a “black box” warning to all botulinum toxin containing meidcations, which is the strongest warning that can be placed on a prescription medication. In addition, a Risk Evaluation and Mitigation Strategy will be developed that includes a Medication Guide to be provided for doctors and patients about the Botox risks.

Manufacturers will also be required to collect safety data on adults and children with muscle spasticity to assess the risk of distant spread of toxin effects, which can cause symptoms of botulism like muscle weakness, respiratory problems, slurred speech, loss of bladder control, difficulty swallowing, double or blurred vision, dry mouth and drooping eyelids.

The apparent increased risk of cerebral palsy Botox problems appear to be associated with the higher doses used to treat the muscle spasticity.

Cerebral palsy is a condition caused by brain damage that is sustained immediately before, during or after birth, that leads to impaired cognitive and motor ability. Botox is sometimes used to help relax muscle spasms associated with cerebral palsy by preventing muscle contraction.

In 2008, Botox sales were $1.3 billion and nearly 2.5 million Americans received a Botox injetion. The warnings also apply to Myobloc, which was approved in 2000 for treatment of cervical dystonia, and Dysport, which was just recently approved for wrinkle smoothing and cervical dystonia.

The FDA has indicated that doctors who use botulinum toxin products should understand that doses are different and not interchangable between products. The new warnings are designed to better inform the doctors of the risk of Botox side effects, so that they can educate their patients about symptoms associated with the spread of the toxin and advise them to obtain immediate medical treatment if symptoms appear.

The Botox black box warning was issued after the prominent consumer advocacy group Public Citizen called for the warnings last year. They indicated that at least 180 reports of Myobloc and Botox side effects were reported to the FDA between 1997 and 2006, including the deaths of 12 adults and 4 children.