Fluoroquinolones are broad-spectrum antibiotics frequently used for the treatment of bacterial infections, particularly those of the urogenital tract and pelvic organs. Other indications include patients with sickle-cell anemia who are at risk for bone infections and hospital patients with pneumonia. They have been associated with a dangerous, life-threatening injury known as aortic aneurysm, among other side effects. In the most serious cases, this can require emergency surgery.

The term “aneurysm” refers to any part of an artery that is weakened and at risk of rupturing. When this occurs in the main artery leading from the heart muscle, it is known as an aortic, or thoracic aneurysm. In some cases, these injuries are minor and grow so slowly that they never cause any real problems. However, one that is larger and fast-growing can lead to a tear in the arterial wall, resulting in serious internal bleeding.

Although fluoroquinolone antibiotics have been in use for more than three decades, it has only been in recent years that the FDA has been alerting the public to dangerous side effects associated with these medications. In 2008, the first boxed warning was required, advising patients of the risk of tendonitis and tendon rupture.

In May 2016, a general warning was issued regarding the possible consequences involving tendons, muscles, joints and the nervous system – including peripheral neuropathy (nerve damage in the extremities). Over the next two years, the FDA received reports of patients who had been given fluoroquinolones and had experiencing retinal detachment and aortic aneurysm. In May of 2017, the FDA issued a statement advising the public that “findings from published studies currently do not support reports that these medicines” are responsible for the injuries in question.

That has changed. On December 20, 2018, the FDA published its latest safety announcement. An agency review has found that use of fluoroquinolone drugs can indeed elevate a patient’s risk of experiencing an aortic aneurysm. Warnings to this extent are now required with prescribing information and the medication guides for all fluoroquinolones. The FDA also advises that such medications be used only as a last resort, particularly on patients who have a history of an aneurysm, hypertension, or any congenital disorders that may weaken blood vessels.

Last July, the FDA issued an updated warning about links between fluoroquinolones and mental health as well as the risk of dangerously low glucose levels (hypoglycemia). Fluoroquinolone antibiotics approved for use in the U.S. are sold under the following brand names:

  • Cipro, Ciloxan, Neofloxin (ciprofloxacin)
  • Tequin, Zymar (gatifloxacin)
  • Levaquin, Tavanic, Iquix (levofloxacin)
  • Avelox, Vigamox, Moxeza (moxifloxacin)

Currently, a class action lawsuit is underway against drug manufacturers, alleging that they had knowledge of fluoroquinolone risks and failed to inform patients and the medical community.

K.J. McElrath is a former history and social studies teacher who has long maintained a keen interest in legal and social issues. In addition to writing for The Ring of Fire, he is the author of two published novels: Tamanous Cooley, a darkly comic environmental twist on Dante's Inferno, and The Missionary's Wife, a story of the conflict between human nature and fundamentalist religious dogma. When not engaged in journalistic or literary pursuits, K.J. works as an entertainer and film composer.