The U.S. Food and Drug Administration (FDA) has warned the public of concerns of serious fluoroquinolone side effects, including peripheral neuropathy.

In addition to the warning, the FDA mandated changes to the labeling of some fluoroquinolone antibiotics to include peripheral neuropathy. Peripheral neuropathy is a type of nerve damage. It usually happens in the hands and feet, though it can occur elsewhere.

As nerve cells die or falter, they can produce a variety of symptoms, including pain, numbness and tingling. A variety of diseases, disorders and injuries can cause peripheral neuropathy. The FDA’s statements and updated drug warnings have advised that the fluoroquinolone antibiotics may be cause peripheral neuropathy. According to the Mayo Clinic, peripheral neuropathy may clear up if the underlying cause of the problem is fixed.

Fluoroquinolones are a group within the quinolone family of antibiotics. This family of antibiotics is primarily synthetic in nature, unlike earlier classes of antibiotics that were either natural compounds or based on natural compounds. They were first developed in hopes that their artificial nature would make it harder for bacteria to adapt to them. While they have proven to have the same problems with resistance as other antibiotics, fluoroquinolones have fared well. However, the FDA’s announcement indicates that the drugs may have serious fluoroquinolone side effects. This group of antibiotics includes Cipro, Levaquin, and Avelox.

The FDA based its warning on reports filed through the Adverse Event Reporting System, a database the agency uses to track unforeseen consequences of drugs. In the past, AERS data has led to recalls and black box warnings. Through AERS, the FDA received reports that patients taking fluoroquinolones suffered peripheral neuropathy, sometimes days after beginning treatment with fluoroquinolones. According to the FDA, these reports included patients that continued to experience peripheral neuropathy for up to a year after they stopped taking fluoroquinolones. Based on this initial data, the FDA was not able to find any factors that made it easier to predict what patients will develop peripheral neuropathy from fluoroquinolones.

A class action lawsuit investigation has been launched to explore the possibility of legal action against the makers of fluoroquinolone antibiotics. Similar lawsuits against drug makers have alleged that drug makers have failed to adequately protect the public from possible fluoroquinolone side effects like peripheral neuropathy. Drug makers are legally obligated to both thoroughly test their drugs for efficacy and safety and to monitor systems like AERS for signs that their drugs have unforeseen consequences, as clinical trials do not always reveal serious side effects due to relatively small sample size.