Avelox Liver Injury Warning Issued in Canada

Canadian drug reviewers are warning doctors to watch out for the potential risk of a liver injury from Avelox, an antibiotic that health officials in Canada say can lead to liver failure and death. 

Health Canada issued the Avelox liver injury warning to health care professionals on Monday, following a safety review of Avelox side effects. The reviewers concluded that Avelox can cause rare, but potentially fatal, liver injury and liver failure.

Health Canada is requiring Bayer to update the label warnings of the drug in Canada to include the association with severe liver injury.

Avelox (moxifloxacin) is an antibiotic sold by Bayer, which was approved in the United States by the FDA in 1999. It is currently sold in more than 80 countries. Avelox is a member of a family of drugs known as fluoroquinolones, which includes other antibiotics such as Levaquin, Cipro, Proquin, and Floxin. They are used to prevent infection by stopping the reproduction of bacteria and are a popular class of medications.

All of the drugs of this class have been linked with an increased risk of tendon ruptures, but the risk appears to be greatest with Ortho-McNeil-Janssen Pharmaceuticals, Inc.’s Levaquin (levofloxacin). According to reports received by the FDA, Levaquin tendon ruptures accounted for 61% of all fluoroquinolone-associated ruptures between November 1997 and December 2005. However, the drug only accounted for about 45% of all prescriptions written for fluoroquinolones during that time.

Fluoroquinolones, as a group, were also linked to vision problems by a September 2010 study by researchers from the Casey Eye Institute in Oregon. They found that the drugs could cause double vision, a condition that goes away when patients stop taking the drug.