The U.S. Food & Drug Administration (FDA) will now require manufacturers of licensed botulinum toxin products to strengthen warnings on product labels that warn healthcare professionals about some of the adverse risks associated with the drug.

Details of the new warnings

The new warnings come after the FDA initiated a safety review of the botulinum toxin – which is sold commercially under the names Botox and Botox Cosmetic (Botulinum toxin Type A), Myobloc (Botulinum toxin Type B), and Dysport (abobotulinumtoxinA) – in February of 2008 after receiving reports of adverse reactions to the drug from the consumer advocate group, Public Citizen. The group had informed the FDA that the use of these drugs have been linked to 16 deaths and 180 reports of serious injury such as aspiration (fluid in the lungs), dysphagia (difficulty swallowing) and/or pneumonia and that 87 cases required hospitalization.

The FDA investigated those allegations and will now require manufacturers to strengthen warnings in product labeling and add a boxed warning regarding the risk of adverse events when the effects of the toxin spread beyond the site where it was injected.

In addition, the FDA will also require manufacturers to “develop and implement a Risk Evaluation and Mitigation Strategy [REMS], including a communication plan to provide more information regarding the risk for distant spread of botulinum toxin effects after local injection, as well as information to explain that botulinum toxin products cannot be interchanged.”

Finally, the REMS must also include “a Medication Guide that explains the risks to patients, their families, and caregivers. FDA is requiring the manufacturers to submit safety data after multiple administrations of the product in a specified number of children and adults with spasticity to assess the signal of serious risk regarding distant spread of toxin effects.”

FDA recommendations

In addition to the stronger warnings, the FDA also says that it “continues to support the recommendations made in its 2008 Early Communication that healthcare professionals” who use the product should:

• Understand that dosage strength (potency) expressed in “Units” or “U” are different among the botulinum toxin products; clinical doses expressed in units are not interchangeable from one botulinum toxin product to another.
• Be alert to and educate patients and caregivers about potential adverse events due to distant spread of botulinum toxin effects following local injections including: unexpected loss of strength or muscle weakness, hoarseness or trouble talking (dysphonia), trouble saying words clearly (dysarthria), loss of bladder control, trouble breathing, trouble swallowing, double vision, blurred vision and drooping eyelids.
• Understand that these adverse events have been reported as early as several hours and as late as several weeks after treatment. Advise patients to seek immediate medical attention if they develop any of these symptoms.

Click here to view the FDA's warning.

If you've been injured by botulinum toxins, contact an experienced drug litigation attorney to discuss your situation and evaluate your options.