Avelox (moxifloxacin) and Levaquin (levofloxacin) are commonly prescribed “quinolone” antibiotics often used for bacterial infections such as respiratory infections, sinus infections and others. However, both the European Medicines Agency and Health Canada have issued warnings about the risk of liver injury from Avelox and Levaquin.

Researchers from the Institute for Clinical Evaluative Sciences (ICES), the University of Toronto and McMaster University examined the risk of acute liver injury in elderly patients taking Avelox compared with those taking other antibiotics commonly used to treat respiratory tract infections.

They looked at 9 years of data from Ontario to identify people aged 66 years or older with no history of liver disease who were admitted to hospital for liver injury within 30 days after receiving a prescription for these antibiotics. Excluding patients admitted for previous liver disease or recent hospitalization, 144 patients were admitted for acute liver injury, with the median time from the dispensing of the antibiotic to admission to hospital being 9 days. Eighty-eight (61.1%) patients died during their admission to hospital for liver injury.

Avelox was associated with a more than 2-fold increased risk of admission to hospital for acute liver injury and Levofloxacin was also associated with a statistically significant but lower risk of liver damage than Avelox

The researchers believe their findings are an important contribution to the evidence regarding the risks of quinolone antibiotics. Despite recent regulatory warnings regarding the safety of Avelox, there is a lack of controlled studies supporting the notion that Avelox presents a particular risk relative to other broad-spectrum antibiotic agents and, in particular, to other quinolones. Although the results require confirmation in other settings, the findings suggest that both Avelox and Levaquin be considered for regulatory warnings regarding acute liver injury.

About Quinolones

Quinolones are among the most widely prescribed antibiotics in the United States. The best known quinolones are Levaquin (levofloxacin) and Avelox (moxifloxacin), but quinolone antibiotics are sold under numerous other generic and brand names. Despite their popularity, quinolones have been linked to serious and sometimes life-threatening side effects, including:

• Liver toxicity
• Liver failure
• Stevens Johnson Syndrome (SJS)
• Toxic Epidermal Necrolysis (TEN)

The pharmaceutical industry is extremely familiar with Avelox and Levaquin as these are often the first medications that physicians choose when their patients are in need of an antibiotic. Sources from WebMD stated that approximately 23 million patients obtained a prescription for Avelox or Levaquin in just the year 2011.

The notable thing about quinolones is that there is increasing evidence that suggests these antibiotics are dangerous. According to several studies and the Food and Drug Administration’s (FDA) announcements, quinolones could possibly cause people who have taken these drugs can suffer from liver damage and liver failure.

Part of the problem is that quinolone antibiotics are often inappropriately prescribed. Instead of being reserved for use against serious, perhaps life-threatening bacterial infections like hospital-acquired pneumonia, these antibiotics are frequently prescribed for sinusitis, bronchitis, earaches and other ailments that may resolve on their own or can be treated with less potent drugs or nondrug remedies.

Quinolone Lawsuits

At first, only a couple patients sought a drug lawsuit lawyer and initiated legal action in the U.S. federal court system, but there are now more than 2,000 who have done so. Legal analysts expect this list to keep growing. The Avelox and Levaquin lawsuits are similar in the fact that they allege patients experienced acute liver failure or Stevens Johnson Syndrome because they took an antibiotic classified in the quinolones category.