What is trimetazidine, the drug found in Russian skater Kamila Valieva's system?

Russian star figure skater Kamila Valieva is at the center of the first big doping case of the Beijing Olympics for a little-known drug she apparently ingested weeks before winning gold in the 2022 competitions.

The 15-year-old athlete tested positive in December for trimetazidine, a drug typically prescribed to much older patients suffering from angina and other heart-related conditions.

But the violation didn't come to light until after Valieva placed first in the first part of the individual competition. According to the ITA, the skater's sample was collected by the Russian Anti-Doping Agency on Dec. 25. However, the World Anti-Doping Agency (WADA)-accredited Swedish laboratory that analyzed it didn't report its results until Feb. 8.

That triggered an immediate suspension from the Games and the medal ceremony to award the Russian team its gold medals in the team figure skating competition was delayed. Valieva successfully appealed the suspension and the favorite was allowed to compete again on Tuesday in the women's individual competition, in which she finished at the top of the standings after the women's short program.

Her lawyer has claimed that Valieva had inadvertently ingested trimetazidine, also called TMZ. The medication belonged to her grandfather and she somehow became contaminated, according to the attorney. The argument swayed the three CAS judges who allowed her to continue to compete at the Olympics.

What is trimetazidine?

TMZ is used in patients to treat chest pain stemming from a lack of blood supply and oxygen to the heart. It is not approved for use in the United States but is approved as an angina therapy in Europe.

"The drug helps in the metabolism of fatty acids. And by doing so, it can actually help the ability of the body to use oxygen, which can help performance and help relieve those chest pains brought on by the blocked blood vessels," Eugene DePasquale, a cardiologist with Keck Medicine of the University of Southern California, told NPR.

It is not recommended for children 18 years or younger. Some side effects include dizziness, headache, abdominal pain and diarrhea. In rare instances it can lead to fast or irregular heartbeats, light headedness or fainting and malaise.

It was added to WADA's list of prohibited substances in 2014. WADA categorizes it as "hormone and metabolic modulator," making it illegal for athletes in and out of competition.

"If you increase the blood flow to the heart, you could potentially increase the performance of the heart, which may in turn enhance the performance of an athlete, DePasquale explained.

But, he added, it's unclear whether that is true in practice because it has yet to be studied. "And certainly for an elite athlete, this may not make much of a difference," DePasquale added.

He also noted many of the drug's side effects — dizziness and loss of balance — which he said, could derail an athlete's performance.

"Yes, there are potential positives but there are also a lot of potential negatives," DePasquale added.

Can TMZ be inadvertently ingested?

Valieva's lawyers successfully raised doubts about the Olympian's guilt, according to The Associated Press, suggesting that the judges believed she might not have intentionally ingested the drug.

USA Today reported one theory posed by the star skater's legal team, was that she could have taken the heart medication by "sipping from the same glass of water as her grandfather."

DePasquale said that is unlikely.

TMZ is an oral medication, which means it would be difficult to take inadvertently. But it's possible "the medication could have been dissolved in a glass of water," he said. Though he noted it's typically taken as a pill.

Other Olympians have tested positive for the drug

In 2018, bobsledder Nadezhda Sergeeva – also from Russia – tested positive for TMZ and was disqualified from the Winter Olympic Games in Pyeongchang.

Sergeeva admitted to the violation and "accepted a provisional suspension beyond the period of the Games," the Court of Arbitration for Sport said at the time.

Chinese star swimmer Sun Yang, also tested positive for the drug in 2014. At the time, Yang's doctor argued the champion swimmer suffered from heart palpitations and dizziness and had been prescribed the drug starting in 2008.

The Court of Arbitration for Sport eventually banned Yang from competition for eight years in 2020 after he was again found guilty of violating anti-doping rules. The court said Yang had failed to cooperate with officials who tried to collect his blood for testing in 2018.

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