Meldonium, the newly banned substance former world tennis number one Maria Sharapova has admitted to taking for 10 years, is reportedly only meant to be used for 'four to six weeks' at a time.
According to a statement emailed to the Associated Press the manufacturers of the drug said it is usually only administered for a short time but prescriptions can be repeated two or three times a year under medical advisement.
It is unclear whether Sharapova took the drug consistently for long periods over the last decade or whether the use of the substance was intermittent.
Depending on the patient's health condition, treatment course of meldonium preparations may vary from four to six weeks.
Treatment course can be repeated twice or thrice a year. Only physicians can follow and evaluate patient's health condition and state whether the patient should use meldonium for a longer period of time.
Evian has announced that is 'closely' following developments in the investigation into tennis star Maria Sharapova after she announced yesterday that she had failed a drugs test.
It comes as Sharapova lost her sponsorship deals with Nike, Tag Heuer and Porsche following the revelations.
The parent company of the water brand, Danone, said it was "surprised" after the star admitted taking what is now a banned medication but did not comment directly on the status of her current sponsorship deal.
Evian has been a partner of Maria Sharapova for many years, and until now, we have maintained a trustworthy professional relationship.
Evian attaches great importance to health, to integrity, and transparency, and we will follow closely the development of the investigation.
Caroline Wozniacki has said that athletes should make sure they "double, triple and quadruple check" their medications following revelations tennis star Maria Sharapova has failed a drugs test.
Speaking at a press conference in New York the Danish tennis star said athletes should be careful to check their medications for banned substances "because sometimes even things like cough drops and nasal sprays can be on the list".
Any time we take any medication I think we double and triple and quadruple check because sometimes even things like cough drops and nasal sprays can be on the list.
So I think as athletes we always make sure to really make sure there is nothing in it that could put us in a bad situation.
Serena Williams said she was "surprised and shocked" like everyone else to hear that fellow tennis player Maria Sharapova had failed a drugs test but praised her honesty in coming forward.
The women's world No. 1 tennis player said: "I think like everyone else said most people were surprised and shocked by Maria.
"But at the same time I think most people were happy that she was upfront and very honest and showed a lot of courage to admit to what she had done and what she had neglected to look at."
A member of the Russia men's volleyball team has reportedly tested positive for the same banned substance as Maria Sharapova.
The R-Sport news agency said meldonium had been detected in a sample given by 25-year-old Alexander Markin.
Russia's sports minister had earlier predicted more cases would emerge involving the nation's athletes in the wake of Sharapova's failed test.
Porsche has become the latest sponsor to change its relationship with Maria Sharapova after she announced she had failed a drugs test at the Australian Open.
The sports car manufacturer said it had postponed all planned activities with the five-time Grand Slam champion until further details are released.
The International Tennis Federation (ITF) is due to issue a final decision on a recommended punishment for Sharapova, which will be reviewed by the World Anti-Doping Agency.
There will be more cases of Russian sports people testing positive for the banned substance meldonium after Maria Sharapova, the nation's sports minister has said.
"It's not my position to make public announcements, but there will be more cases," the R-Sport agency cited Mutko as saying.
Commenting on Sharapova's case, he said: "I think (she) will sort it out herself."
Russia's tennis chief Shamil Tarpishchev said he expects Sharapova to compete at this summer's Olympics in Rio and described her failed test as "a load of nonsense".
Mutko, though, said his ministry had warned the nation's athletes before about meldonium being outlawed by the World Anti-Doping Agency.
He said Russia needs three to four years to restore order to its sports anti-doping regime and promised to implement tough measures.
Swiss watch manufacturer Tag Heuer has said it will not renew its sponsorship deal with Maria Sharapova after she failed a drug test.
The tennis star admitted taking a banned substance and has been suspended from the sport while awaiting her punishment.
Tag Heuer's decision came after Nike suspended its relationship with the 28-year-old Russian.
According to Forbes, Sharapova's 2015 earnings of $29.5 million (£20.7 million) came mostly from endorsements.
Maria Sharapova admitted she failed to click on an email attachment informing her the drug she had taken for 10 years was now prohibited.Read the full story ›
Maria Sharapova's former coach Jeff Tarango has told ITV News he believes the blame for her failed drugs test lies with the people "she pays close to $1 million to hang out with her".
He said it is "believable" the five-time Grand Slam champion would have been unaware of last year's change of rules regarding the drug meldonium, which came into effect this year.