By Brad Broker
The U.S. Food and Drug Administration on Friday issued a formal warning to consumers that hydroxychloroquine and chloroquine — the antimalarial drugs touted by President Trump as a cure-all for COVID-19 — should not be used outside of a hospital setting to treat the novel coronavirus.
“Hydroxychloroquine and chloroquine have not been shown to be safe and effective for treating or preventing COVID-19,” said the FDA in its statement. “They are being studied in clinical trials for COVID-19, and we authorized their temporary use during the COVID-19 pandemic for treatment of the virus in hospitalized patients when clinical trials are not available.”
Several studies have shown that hydroxychloroquine has led to higher death rates in patients confirmed with COVID-19.
“Hydroxychloroquine and chloroquine can cause abnormal heart rhythms such as QT interval prolongation and a dangerously rapid heart rate called ventricular tachycardia,” said the FDA. “Patients who also have other health issues such as heart and kidney disease are likely to be at increased risk of these heart problems when receiving these medicines.”
Patients using hydroxychloroquine for conditions including malaria or autoimmune diseases such as lupus should continue to use the medicine as prescribed.
Physicians should be aware that hydroxychloroquine or chloroquine can:
- cause QT prolongation
- increase the risk of QT prolongation in patients with renal insufficiency or failure
- increase insulin levels and insulin action causing increased risk of severe hypoglycemia
- cause hemolysis in patients with Glucose-6-Phosphate Dehydrogenase (G6PD) deficiency
- interact with other medicines that cause QT prolongation even after discontinuing the medicines due to their long half-lives of approximately 30-60 days
As for the novel coronavirus, the FDA warns that “there are no proven treatments for COVID-19 and no vaccine.”