Lee, et al. (2020) [40]  Single-center clinical study211 individuals exposed to COVID-19  400 mg day of HCQ as post-exposure prophylaxis14 days  At the end 14 days of quarantine, there was negative follow-up PRC tests.  The most common side effects were diarrhea or loose stool (9%), skin rash (4.3%), gastrointestinal upset (0.95%) and, bradycardia (0.95%). In 5 patients (2.7%) post-exposure prophylaxis was discontinued due to bradycardia (2), gastrointestinal upset (2), and the need for fasting (1).  There was not a control group and the study was carried out at a single center.