Maria Sharapova's Failed Doping Test: What Is Meldonium?
Maria Sharapova practices at the 2016 Australian Open.
Credit: Jimmie48 Photography / Shutterstock.com

Tennis star Maria Sharapova has been provisionally suspended from competition after testing positive for the recently banned drug meldonium. But what exactly does this drug do, and can it really enhance athletic performance?

On Monday (March 7), Sharapova admitted to failing a drug test for the upcoming Australian Open because she had been taking meldonium (sold under the brand name Mildronate). Sharapova said she had been taking the drug for 10 years as advised by her family doctor. The World Anti-Doping Agency (WADA) added meldonium to the list of prohibited substances as of Jan. 1, 2016.

Sharapova said she started taking the medication in 2006, following a variety of symptoms, including frequent bouts of the flu; an irregular EKG (electrocardiogram, a test that assesses the heart's electrical activity); magnesium deficiency; and "indications of diabetes," a disease she said runs in her family. [The 16 Oddest Medical Case Reports]

Mildronate is made by the Baltic pharmaceutical company Grindeks. The drug is not approved in the United States or Western Europe, but it is available over the counter and as a prescription in Eastern Europe. Earlier this month, Grindeks released a statement protesting the WADA's ban on Mildronate — and clarifying that the company is not the only manufacturer of drugs that contain meldonium.

In the statement, the company said that Mildronate is used widely by doctors, mostly for the treatment of heart and cardiovascular diseases, including chronic heart failure, cardiomyopathy (abnormality of the heart muscle) and ischemic circulation disorders (reduced blood flow to certain regions). By making the heart consume carbohydrates in lieu of fatty acids as a source of energy, the drug reduces the amount of oxygen the heart needs, according to Grindeks. This is designed to help prevent muscle tissue damage in times of stress, including periods of increased physical activity.

Grindeks representatives said meldonium is a protective drug meant to guard against cell death, not to increase the performance of normal cells. "Meldonium cannot improve athletic performance, but it can stop tissue damage in the case of ischemia [deficient blood flow to a body part]. That is why it is a therapeutic drug" and doesn't constitute doping, Grindeks representatives said in the statement.

But a review of studies focusing on the effects of Mildronate, published in a booklet from the 5th Baltic Sport Science Conference in 2012, said otherwise. The authors of the review agreed that Mildronate optimizes oxygen consumption for protection against certain heart problems. They added, however, that Mildronate could have many advantageous effects for athletes, such as increased endurance, improved aerobic capabilities and reduced recovery times after physical exertion.

Several scientific papers on meldonium in athletes also include information about how and when to dose the drug in order for patients to obtain the desired effects, said Mario Thevis, a professor of preventive doping research at German Sport University Cologne and a forensic chemist who helped develop the doping test for meldonium. The sports that have been studied for meldonium doping included wrestling, judo, canoeing, rowing and volleyball, Thevis told Live Science in an email. [What If Doping Were Legal?]

Still, although these studies suggest that meldonium enhances athletic performance, there is no definitive evidence of its effects, Christian Schneider, a member of the European Olympic Committees' Medical and Anti-Doping Commission, said in an email interview to Live Science.

In 2015, meldonium was one of two drugs added to the list of those set to be monitored by the WADA due to its possible cardiac stimulant effects. It was the only drug moved from the monitoring program to the prohibited list for 2016.

A data analysis of meldonium use by athletes in the Baku 2015 European Games in Azerbaijan showed that 66 of 762 athletes tested positive for the drug before and during the Games, according to the study published in the British Journal of Sports Medicine, which was co-authored by Schneider. These were athletes competing in 15 different sports (the Games features 21 sports in total), and 13 of these athletes placed within the top three in their competitions.

When asked about the importance of revealing athlete doping, Schneider said, "Fair play should be in all athletes' and supporters', or even spectators', interest … Any use of prohibited help [whether medical, technical or something else] should be known to others."

Sharapova was not the only elite athlete to test positive for meldonium since the ban went into effect. Otherse who are reportedly in situation similar to Sharapova's include: Russian ice dancer and 2014 gold medalist Ekaterina Bobrova; Russian cyclist Eduard Vorganov; Eithiopian-Swedish former world champion 1,500-meter runner Abeba Aregawi; and two Ukrainian biathletes, Olga Abramova and Artem Tyshchenko.

According to a statement from the Tennis Anti-Doping Programme (TADP), Sharapova was charged with an anti-doping rule violation and has been provisionally suspended. Three of her major sponsors — Nike, Tag Heuer and Porsche — have already distanced themselves from the scandal, according to news reports. Forbes has estimated that losing the Nike contract alone would add up to a loss of $17.5 million for the sports star.

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