Hydroxychloroquine, an antimalarial drug, carries risks of ventricular arrhythmias and sudden cardiac death, especially in critically ill individuals.

“hydroxychloroquine is an old off-patent drug that is inexpensive with a known safety profile drug interactions and side-effects it is an anti-malarial therapeutic that is also used to treat rheumatoid arthritis and lupus it's pretty well tolerated however there are safety concerns anti malarial drugs can cause ventricular arrhythmias QT c prolongation which can lead to fatal ventricular arrhythmias and sudden cardiac death and other cardiac toxicity which may oppose particular risk to critically ill persons”