Rio 2016 Olympic bronze medallist weightlifter Izzat Artykov was stripped of his medal on Thursday after being found to have the rat poison strychnine in his system.
The Kyrgyz lifter became the first medallist at these Games to test positive for a banned substance, the Court of Arbitration for Sport said.
Strychnine, a highly toxic alkaloid, is ordinarily used as a pesticide for killing rodents. When ingested, strychnine causes muscular convulsions before death through asphyxia.
Those convulsions had been thought to be beneficial in tiny doses in the past, and in the late 19th and early 20th centuries it was used in small doses as an athletic performance enhancer, and recreational stimulant.
At the 1904 Olympics in St. Louis, Missouri, Thomas Hicks won the marathon thanks in part to several doses of strychnine, egg whites and brandy administered by his trainer mid-race, historians say, in the first recorded instance of drug use in the modern Olympics.
Strychnine, reportedly used widely by cyclists in the early days of the Tour de France, is defined as a stimulant in the World Anti-Doping Agency’s list of banned substances.