The use of chloroquine and its derivatives as an anti-viral agent is supported by pre-clinical in-vitro studies and its clinical safety is known in the term of its other indications. But there is insufficient clinical data to support its use in critically ill patients with The noval corona virus disease 2019 (COVID-19). Nevertheless, it is recommended that these drugs, which are supported by the urgency of the COVID-19 pandemic in many national guidelines and consensus reports, including our country, should be applied in accordance with the guidelines.