Maria Sharapova doping test: What is meldonium and why is the drug banned in tennis?

Five-time Grand Slam champion Maria Sharapova has tested positive for meldonium, a drug recently banned by the World Anti Doping Agency (WADA). The test was carried out by the tennis antidoping programme after Sharapova lost to Serena Williams in the Australia Open quarter finals, on 26 January 2016.

The Russian athlete admitted to taking the drug regularly since 2006, which she knew under its other name, mildronate. Manufactured in Latvia, the drug is mostly used in Eastern European countries to treat ischaemia. This condition is characterised by limited blood flows in the body's tissues, which causes a shortage of oxygen and glucose needed for cellular metabolism.

To solve this problem, the drug's main function is to increase the blood flow. It is thought it could be used by athletes because it can help them increase their resistance and exercise capacity. A study published in December 2015 in Drug Testing and Analysis confirmed this.

The authors looked at data to estimate the prevalence of misuse in professional sports and found meldonium was very often used for non-medical reasons. They argued that meldonium increased "endurance performance of athletes, improved rehabilitation after exercise, protection against stress, and enhanced activations of central nervous system (CNS) functions".

Second case of misuse in a week

The drug was officially banned on 1 January 2016 by WADA after the agency found evidence of its use by athletes to improve their performances.

Sharapova says she took the drug after suffering from various illnesses in the past ten years. Her family has a history of diabetes. "I was getting sick very often, I had a deficiency in magnesium, I had irregular EKG results, and I had a family history of diabetes," she said during a press conference.

She also said she was unaware it had been banned. "I received a letter on 22 December from the World Anti Doping Agency for the changes next year and where the tests will be with a link to the changes for 2016 and I did not look at that list," she said. "I know that with this, I face consequences and I don't want to end my career this way and I hope that will have a chance to play again."

It is the second time meldonium comes into the spotlight in recent days. On 6 March 2016, another Russian athlete, Ekaterina Bobrova, who won an Olympic gold medal for figure skating, also admitted to testing positive to the drug.