Chloroquine was discovered in 1934 by Hans Andersag.[3][4] It is on the World Health Organization's List of Essential Medicines, the medicines needed in a health system that are considered to be the safest and most effective.[5] It is available as a generic medication.[4] The wholesale cost in the developing world is about US$0.04.[6] In the United States, it costs about US$5.30 per dose.[1]