Severe Illness Associated with Using Non-Pharmaceutical Chloroquine Phosphate to Prevent and Treat Coronavirus Disease 2019 (COVID-19)

Chloroquine phosphate, when used without a prescription and supervision of a healthcare provider, can cause serious health consequences, including death. Clinicians and public health officials should discourage the public from misusing non-pharmaceutical chloroquine phosphate (a chemical used in home aquariums). Clinicians should advise patients and the public that chloroquine, and the related compound hydroxychloroquine, should be used only under the supervision of a healthcare provider as prescribed medications.