The fluoroquinolone family of quinolone antibiotics, which include Levaquin, Ciprobay, Cipro, Ciproxin, Maxaquin, Acuatim, Nadoxin, Nadixa, Floxin, Oxaldin and Tarivid, are effective drugs for treating bacterial infections. But the unwanted side effect of joint pain resulting from a toxic buildup of these drugs in the tendons has been problematic in some patients.
Function of Quinolone Antibiotics
Quinolone antibiotics were first developed to treat kidney infections. Since they were initially developed, quinones have been found to be effective for other serious bacterial infections as well. Fluoroquinolones are a family of quinolones that have been particularly useful because they stop DNA replication of the bacteria that cause these infections, keeping bacterial cells from reproducing.
Tendinitis and soft tissue problems are rare among fluoroquinolone antibiotic users. Toxins build up in these tissues, causing pain and sometimes resulting in ruptured tendons. These injuries most often involve the Achilles tendon, but have also occurred in shoulder, biceps, hand and thumb joints. They occur most frequently with long-term use of the drugs. Scientists are still identifying what exactly causes these problems to occur, and what the correlation is between fluoroquinolones and tendon problems.
Between November of 1997 and December of 2005, 262 tendon ruptures, 258 cases of tendonitis and 274 cases of other tendon disorders were recorded in the FDA’s adverse event database. Just under two-thirds of those problems were reported with use of the drug Levaquin. Twenty-three percent of those problems occurred in patients using the drug Cipro.
Litigation and FDA Warnings
A consumer group called Public Citizen recently sued the makers of many fluoroquinolones, demanding that they be required to post black box labels on the packaging of these drugs warning consumers and doctors about the potential for joint problems. They also want makers to send warning letters to physicians to notify them of the potential issues. The FDA has agreed to require black box warning labels on fluoroquinolones. Several class action lawsuits around this issue are pending.
Relief from Pain
Although some patients have suffered severe joint pain after using fluoroquinolones, the good news is that symptoms are easily resolved by discontinuing use of the drugs. There have been no reported long-term joint problems as a result of using fluoroquinolones.
Risks of tendon and ligament swelling and tears are greatest in those over 60 years of age, heart, kidney and lung transplant recipients and among those who are also using steroids. Other substances, including caffeine, theophylline, corticosteroids and non-steroidal anti-inflammatory drugs, have been found to increase the toxicity of fluoroquinolones. Antivirals, antacids and other antibiotics can also cause undesirable drug interactions.