"It's fairly low-level as far as banned substances go - it's sold over-the-counter in Russian and some Eastern European countries...".
It quotes a New York Times article explaining that Russians are baffled that WADA would consider it cheating.
The Times stated: "Russian teams had used the drug regularly and openly, viewing it as a remedy for fending off exhaustion and heart problems. Most team coaches would keep a supply, administering it along with other standard vitamins.
Meldonium was an obscure drug until Sharapova's high-profile fall from grace. But the drug has long been popular with ice hockey players.
Kirovs Lipmans, owner and chairman of the Latvian drug manufacturer Grindeks, told an interviewer in 2011: "I know that the Russian national ice hockey team don't even come to training camps without mildronate, to say nothing of Latvian national team players.
"I presume that in the coming years it will become a very popular drug among athletes...ice hockey players have long taken mildronate, and now Russians are actively breaking into this."