Commonly prescribed antibiotics may be linked to heart problems

Fluoroquinolones may be linked to a greater risk of heart problems, according to a new study published in Journal of the American College of Cardiology. These new findings join a host of possible adverse events associated with the antibiotics, including aortic ruptures and tears, severe drops in blood glucose, tendon ruptures, and mental health effects such as trouble paying attention, disorientation, and memory loss.

In the study by Etminan and colleagues, researchers assessed data from FDA’s adverse reporting system database and U.S. PharMetrics Plus, a massive private insurance health claims database. In a random sample of 9,053,240 patients, they identified and analyzed 12,505 cases of valvular regurgitation and 125,020 case-control participants.

Patients currently taking fluoroquinolones such as ciprofloxacin (Cipro—Pfizer), compared with other antibiotics like amoxicillin and azithromycin, had a 2.4 times greater risk of developing aortic and mitral regurgitation, conditions in which the blood backflows into the heart.

Some physicians favor fluoroquinolones for their broad-spectrum activity and high oral absorption, which allows patients to be prescribed an oral medication for infections that may otherwise require a hospital stay for I.V. treatment.

“This class of antibiotics is very convenient, but for the majority of cases, especially community-related infections, they’re not really needed. The inappropriate prescribing may cause both antibiotic resistance as well as serious heart problems,” said lead study author Mahyar Etminan in a statement. Etminan is associate professor of ophthalmology and visual sciences in the faculty of medicine at the University of British Columbia.

The researchers noted that only current (within the 30 days preceding the cardiac event) and recent (within 31 to 60 days) fluoroquinolone use were associated with aortic and mitral regurgitation, with current use posing the greatest risk. Fluoroquinolone use was not linked to regurgitation in patients who took the antibiotics 61 to 365 days before the cardiac event.

While mild aortic and mitral regurgitation may not have any symptoms, patients with more severe cases may experience heart palpitations, chest pain, fatigue, and shortness of breath. If severe enough and left untreated, regurgitation may lead to heart failure. Pharmacists should be aware of the possible cardiac effects of fluoroquinolones, especially when treating patients who have had a history of cardiac events.