Hydroxychloroquine, azithromycin linked to “potentially lethal” cardiovascular complications

Hydroxychloroquine and azithromycin are both associated with significant cardiovascular complications, and taking them together could be a deadly combination, according to new research published in Circulation.

The two drugs were repeatedly pushed as potential COVID-19 treatments in the early days of the pandemic, and President Donald Trump even claimed to be taking them as recently as May 18, but studies continue to suggest their use should be limited to closely monitored clinical trials.

For this latest study, lead author Lee S. Nguyen, MD, and colleagues explored data related to adverse drug reactions from a World Health Organization database. More than 21 million adverse events were included in the analysis, and more than 76,000 were associated with hydroxychloroquine alone; the hydroxychloroquine was suspected to be responsible in 28.4% of those cases. Azithromycin alone, meanwhile, was associated with more than 89,000 adverse events—and it was suspected to be responsible in 60.8% of those cases. Another 607 adverse event reports were found that were linked to the use of the two drugs together.

Drilling deeper into the findings, Nguyen et al. noted that hydroxychloroquine was linked to the development of conduction disorders and heart failure. Reports of “potentially lethal acute cardiac proarrhythmogenic effects” were also associated with hydroxychloroquine and azithromycin.

“Hydroxychloroquine and azithromycin have increased cardiovascular toxicity, should not be administered outside of a clinical trial, and require close additional cardiovascular monitoring and treatment,” Mariell Jessup, MD, chief science and medical officer of the American Heart Association, said in a prepared statement about the research.

What other researchers, and the FDA, have had to say about these drugs

Hydroxychloroquine and azithromycin have been the focus of numerous studies since first being floated as possible COVID-19 treatments. published in the New England Journal of Medicine, for example, found that “the risk of intubation or death was not significantly higher or lower” among COVID-19 patients treated with hydroxychloroquine. Other researchers have reported that taking hydroxychloroquine, alone or with azithromycin, is associated with an increased risk of QTc prolongation or death.

The FDA also weighed in the potential risks of attempting to treat COVID-19 with hydroxychloroquine and azithromycin, issuing a statement that addresses the topic in great detail.

“The FDA is aware of reports of serious heart rhythm problems in patients with COVID-19 treated with hydroxychloroquine or chloroquine, often in combination with azithromycin and other QT prolonging medicines,” the agency explained in a statement. “We are also aware of increased use of these medicines through outpatient prescriptions. Therefore, we would like to remind health care professionals and patients of the known risks associated with both hydroxychloroquine and chloroquine. We will continue to investigate risks associated with the use of hydroxychloroquine and chloroquine for COVID-19 and communicate publicly when we have more information.”

Michael Walter
Michael Walter, Managing Editor

Michael has more than 18 years of experience as a professional writer and editor. He has written at length about cardiology, radiology, artificial intelligence and other key healthcare topics.

Around the web

Ron Blankstein, MD, professor of radiology, Harvard Medical School, explains the use of artificial intelligence to detect heart disease in non-cardiac CT exams.

Eleven medical societies have signed on to a consensus statement aimed at standardizing imaging for suspected cardiovascular infections.

Kate Hanneman, MD, explains why many vendors and hospitals want to lower radiology's impact on the environment. "Taking steps to reduce the carbon footprint in healthcare isn’t just an opportunity," she said. "It’s also a responsibility."