Meldonium, the same purported performance enhancer that landed tennis star Maria Sharapova in hot water, enjoyed plenty of popularity among athletes who attended the Baku 2015 European Games, a new report from the British Journal of Sport Medicine released January 8 has found.

The authors examined testing results taken during the Games by the World Anti-Doping Agency Monitoring Program. More than 650 athletes at the Games from June 12-28 submitted blood and urine tests before and during the event. Of them, 8.7 percent tested positive for meldonium. Tellingly, only 3 percent of athletes self-reported their use of the drug prior to the test. though meldonium wasn’t placed on the the agency’s prohibited substance list until this January.

“These findings highlight the excessive and inappropriate use and prescribing of this prescription drug in a generally healthy athlete population,” the researchers concluded.

Sharapova announced in a press conference Monday that she tested positive for meldonium during the Australian Open in January, claiming she had often used it since 2006 to help with a number of medical issues, including magnesium deficiency. She also stated she was unaware that it was on the prohibited list, not having read an email sent from the doping agency in December regarding the changes. Sharapova, who is currently injured, was provisionally suspended from the sport by the International Tennis Federation for the failed test, with no word yet on how long the ban will last.

The study authors cautioned that Sharapova may not be alone in being ignorant about meldonium’s now-banned status, and advocated that National Anti-Doping Organizations launch a global awareness campaign aimed towards both athletes and healthcare providers to prevent future violations. “In addition, further education for athletes and their medical support personnel about appropriate prescribing of medical drugs only for legitimate medical care is warranted,” they wrote.

Of course, meldonium isn’t the only relatively obscure drug on the prohibited list.

There’s salbutamol, a long-used asthma drug traditionally available as an inhalant. When injected or taken as a tablet, though, it and other beta2 agonists act more like anabolic steroids. Or dextromoramide, a narcotic more potent than morphine but only available in the Netherlands. While not directly performance enhancers and plenty dangerous when not used correctly, narcotics allow athletes to ignore injuries and stress during competition and push themselves further than expected during training. Let’s not forget pindolol, one of many banned beta-blockers. Beta-blockers dull the effect of adrenaline, in turn allowing competitive archers, race car drivers, and even pool players to stay cooler under pressure with a slower heart beat and reduced anxiety.

Meldonium, the only major addition onto the 2016 ban list, is medically used to increase blood flow, prevent the enlargement of heart muscle, and increase stress tolerance. Strangely enough, though, its status as a bonafide performance enhancer isn’t set in stone.

“The evidence to demonstrate any performance enhancing effects of meldonium in the athlete population is limited,” the study authors noted. “There appears to be some evidence that meldonium may benefit exercise performance in rodents, but specific studies to evaluate potential effect on performance specifically in elite athletes have not been identified.”

Given many healthy athletes’ willingness to take the drug, and their later reluctance to admit to it, though, it’s likely there’s some proof in the pudding. The World Anti-Doping Agency, having previously placed meldonium on its 2015 watch list, apparently thought so too,

Source: Stuart M, Schneider C, Steinbach K. Meldonium use by athletes at the Baku 2015 European Games. British Journal of Sport Medicine. 2016.