Ivermectin is a medication used to treat parasite infestations.[6][7] In humans, these include head lice, scabies, river blindness (onchocerciasis), strongyloidiasis, trichuriasis, ascariasis, and lymphatic filariasis.[6][8][9][10] In veterinary medicine, the medication is used to prevent and treat heartworm and acariasis, among other indications.[9] Ivermectin works through many mechanisms of action that result in the death of the targeted parasites;[6] it can be taken by mouth or applied to the skin for external infestations.[6][11] The drug belongs to the avermectin family of medications.[6]

Ivermectin was discovered in 1975 and came into medical use in 1981;[12][13] William Campbell and Satoshi Omura won the 2015 Nobel Prize in Physiology or Medicine for its discovery and applications.[14] The medication is on the World Health Organization's List of Essential Medicines,[15] and is approved by the U.S. Food and Drug Administration as an antiparasitic agent.[16] In 2018, ivermectin was the 420th most commonly prescribed medication in the United States, with more than one hundred thousand prescriptions.[17] It is available as a generic medicine.[18][19]