Chloroquine and hydroxychloroquine are being explored as possible treatment options for the COVID-19 coronavirus and have been hailed by President Trump as a “gamechanger.” However, some health officials and researchers have concerns about the drug and its efficacy in treating COVID-19 patients, and others have pointed out that the side effects with different dosages are potentially serious.

The FDA has already given hospitals an emergency authorization to use chloroquine and its more widely used version of hydroxychloroquine to treat COVID-19. Both are drugs normally used to treat malaria. A study of chloroquine in Brazil that involved a higher dose of the drug has been halted after 11 patients who were given the higher dose died.

The Small Study Has Been Halted Due to the Risk of Possibly Fatal Heart Rate Changes

The New York Times first reported on the small research study in Brazil, which found that coronavirus patients who were taking a higher dose of chloroquine were developing irregular heart rates, putting them at a higher risk of a fatal heart arrhythmia.

The government-sponsored study in Brazil involved 81 coronavirus patients in the hospital. According to the report cited by the Times, “infectious disease doctors and drug safety experts said the study provided further evidence that chloroquine and hydroxychloroquine can pose significant harm to some patients, specifically the risk of a fatal heart arrhythmia.”

In response to the study, Dr. David Juurlink, the head of the division of clinical pharmacology at the University of Toronto, said: “To me, this study conveys one useful piece of information, which is that chloroquine causes a dose-dependent increase in an abnormality in the [electrocardiogram] that could predispose people to sudden cardiac death.” Electrocardiograms are used to read a person’s heart activity.

During the study, half of the patients were given the standard dose of 450 milligrams of chloroquine two times a day for five days, and the others were given a higher dose of 600 milligrams over 10 days. In three days, researchers were already noticing irregular heart rates in the patients on the higher dose, and by day six, 11 of them had died. The higher dose portion of the trial was immediately stopped. Researchers were not able to determine if the lower dose of chloroquine was effective in treating coronavirus.

Tom Hanks’ Wife Rita Wilson Says She Was Given Chloroquine & Experienced ‘Extreme’ Side Effects

Rita Wilson, Tom Hanks’ wife, says when the two were in the hospital in Australia after testing positive for COVID-19, she was given chloroquine as a treatment. She told CBS News that the drug gave her extreme side effects and urged caution to people using the drug as a coronavirus treatment. It’s unclear what dosage of chloroquine she received.

She told Gayle King: “I can only tell you that I don’t know if the drug worked or if it was just time for the fever to break. The fever did break, but the chloroquine had such extreme side effects I was completely nauseous and I had vertigo and my muscles felt very weak.” She added, “I think people have to be very considerate about that drug. We don’t really know if it is helpful in this case.”

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