A study in Brazil using chloroquine  was halted as it causes heart complications in patients and killing two, proving it might not be the 'game-changer' it hoped to be.

Since the endorsement of chloroquine in several studies to prove it is 'not anecdotal', a Brazilian test of the drug resulted in shocking results. One group of patients given the anti-malaria drug had cardiac problems caused by taking the drug, which means it may have deadly side effects.

Chloroquine: not the miracle cure we're hoping?

The dosage given to these patients were quite high, and chloroquine is not one of those drugs meant for COVID-19. Experts learned that the treatment is not successful as the anti-malaria drug is an anti-parasitic drug, not an anti-viral.

Brazilians researchers are intent on proving that chloroquine is a safe cure for COVID-19. As many as 440 people were to enrol in the study to prove that results from China were legitimate, hoping the study will yield positive results.

Those who were in the drug trials were given a high dose of chloroquine (600 milligrams 2x a day for 10 days), and a low dose (450 mg 5x a day, double dose on the first take). It was meant as a 'double-blind', so neither the doctors or patients knew what dosage went to whom.

Failure of clinical trials in high dosage

It did not go smoothly, with only 81 patients enrolled who exhibited alarming signs that chloroquine is not a 'game-changer'. Soon after the trials were underway, the treatments went sideways and caused alarm for the researchers.

A few days later, the patients of the high dose group (600 milligrams) were having heart rhythm problems, compared to the low dosers (450 mg.) who fare better.

Soon after the symptoms were detected in the high dosers, two in the group had died but they had an abnormal heart rate known as ventricular tachycardia before getting deceased.

Taking chloroquine or hydroxychloroquine has the side effect of causing irregular heartbeats, caused by altering the electro-impulses in the heart muscle. At times, this is serious and can even be fatal.

The unwitting death of two subjects, with heart problems, cause the high dose to be dropped from the study. A bulletin was issued to avoid high doses for COVID-19 patients.

Also read: Anti-Body Based COVID-19 Drugs May Have More Advantages Than Drug Based-Cures Like Hydroxychloroquine 

Is it worth the risk?

Researchers in the study later warned that futures trials should not include high doses to avoid disastrous effects. They posted the findings on April 11 to pre-print database medRxiv, not published in a peer-review journal yet.

One hospital in France stopped giving hydroxychloroquine to one COVID-19 patient as it affects the cardiac cycle, reported News Week.

Chloroquine and hydroxychloroquine are used for treating malaria, works most of the time but can sometimes cause a heart condition 'QT prolongation'. Never use it unless supervised or else it can be fatal for those with heart conditions.

The combination of azithromycin and hydroxychloroquine is also being used in hospitals in the United States, The New York Times reported. There is still a risk of symptoms to worry about. Later, all subjects in the study were in low dose groups, but chloroquine that causes heart complications is now under study if it is truly suitable for treating COVID-19.

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