Ciprofloxacin (Cipro) is a widely used antibiotic prescribed to treat several life-threatening bacterial infections. First introduced by Bayer in 1987, Cipro is part of a class of antibiotics known as fluoroquionlones. Millions of Americans continue to be prescribed Cipro each year, and it is one of the best selling antibiotics on the market.

However, research shows the antibiotic ciprofloxacin — sold primarily under the brand name Cipro, but also as Ciflox, Ciloxan, Baycip, Ciproxin, Prociflor, Ciprex, and Proquin — can cause nerve damage and other harmful ciprofloxacin side effects.

Ciprofloxacin and Nerve Damage

Although information about the link between Cipro and peripheral neuropathy or nerve damage has been known for years, drug warnings provided with the antibiotic were inadequate and misleading, suggesting that problems with nerve damage were “rare” and failing to disclose that users may be left with long-term effects that impact them for the rest of their life.

Peripheral neuropathy from Cipro may cause damage to the peripheral nervous system, leaving users with persistent weakness, numbness and pain. Symptoms of Cipro nerve damage may include:

• Numbness in extremities
• Burning pain
• Sharp, jabbing or electric-like pain
• Extreme sensitivity to touch
• Changes in skin, hair or nails
• Loss of coordination
• Muscle weakness or paralysis
• Heat intolerance
• Bowel and bladder problems
• Dizziness, lightheadedness

While the nerve problems often first develop as pain or discomfort in the hands and feet, the issues may continue to move up the limbs and cause more serious and permanent injuries.

Some U.S. veterans have stepped forward to say that they believe that Gulf War Syndrome, which often involves nerve damage and peripheral neuropathy, could be the result of large doses of ciprofloxacin they were given during war.

In August 2013, the U.S. Food and Drug Administration (FDA) issued a drug safety communication advising the public that it was requiring a label change to Cipro and other fluoroquinolone antibiotics to “better describe the serious side effect of peripheral neuropathy,” which is the medical term for potentially permanent nerve damage. Peripheral neuropathy can occur soon after ciprofloxacin treatment begins.

Ciprofloxacin Side Effects

In addition to being linked to peripheral neuropathy, Cipro has been linked to the following serious side effects:

• Muscle weakness
• Tendon ruptures
• Central nervous system disorders
• Tremors
• Restlessness
• Lightheadedness
• Confusion
• Hypersensitivity reactions
• Loss of consciousness
• Cardiovascular collapse
• Life-threatening skin reactions
• Toxic epidermal necrolysis (TEN)
• Stevens-Johnson syndrome (SJS)
• Clostridium difficile associated diarrhea

Cipro FDA Black Box Warning

The FDA allegedly did not act quickly on its promise in mandating Cipro label warnings, however. In 2005 and 2006, the consumer advocacy group Public Citizen and the Attorney General of Illinois petitioned the FDA to require a “black box” Cipro warning.

In 2008, both petitioners finally sued the FDA to require the Cipro warnings, and on Sept. 8, 2008, the FDA required Bayer and other ciprofloxacin manufacturers to include a black box warning on packages of Cipro, informing the public of dangerous side effects that the drug causes.

There are fears that Cipro is over-prescribed and is now no longer effective because bacteria have developed resistances to it. Indeed, fluoroquinolones are among the most prescribed antibiotics in the United States even though the FDA requires that they be used only as a therapy of last resort. Frequently, they are even used to treat conditions they aren’t approved for.