Clarithromycin Side Effects Linked to Heart Problems For Those with COPD

Side effects of the antibiotic clarithromycin, which is most commonly known as Biaxin, could be linked to a risk of serious and potentially life-threatening heart problems, according to researchers from Australia and the United Kingdom. 

In a study published last week by the British Medical Journal, researchers found that patients given Biaxin or other antibiotics containing clarithomycin were 50% more likely to suffer a cardiovascular event or cardiovascular death.

Researchers looked at data on about 3,000 patients admitted to one of a dozen hospitals in the United Kingdom between 2009 and 2011. They found a 50% increased risk of cardiovascular events and acute coronary syndrome among patients given clarithromycin. They also found a 52% increase in the risk of cardiovascular mortality when given to patients suffering from chronic obstructive pulmonary disease (COPD), but not with patients given the antibiotic for the treatment of pneumonia.

The drug belongs to a class of antibiotics known as macrolides. Zithromax (azithromycin) is another antibiotic in the same class, which has also recently been linked to a risk of heart problems.

“Evidence is accumulating for long term cardiovascular risks associated with macrolides,” the researchers concluded. “Our data would support the need for a high quality randomized controlled trial of macrolides with long term follow-up.”

Earlier this month the FDA issued a warning about the potential side effects of Zithromax, indicating that the antibiotic may disrupt the electrical activity of the heart. Zithromax is also known as the Z-Pak or Zmax.

A May 2012 study published in the New England Journal of Medicine first warned about the potential heart risks with Zithromax. Researchers found patients were 2.5 times more likely to die due to heart related problems on a five day Zithromax treatment when they compared it to treatment with other antibiotics or no antibiotic therapy.

The FDA review found that certain patients were more at risk, including those with existing QT interval prolongation, patients with low blood levels of potassium or magnesium, patients with slower than normal heart rates, and those taking certain drugs used to treat abnormal heart rhythms.