The NHL has added meldonium to its list of banned substances.

Deputy commissioner Bill Daly confirmed the addition in an email to The Associated Press on Wednesday. It was first reported by the Russian news agency TASS.

The change goes into effect for the upcoming season. The NHL and NHL Players' Association had to agree to add meldonium to its list of prohibited substances.

Daly says that decision was made for the same reason the World Anti-Doping Agency banned meldonium on Jan. 1.

Tennis star Maria Sharapova and swimmer Yulia Efimova have tested positive in recent months for the endurance-boosting drug. Sharapova is appealing her two-year ban.

Russia switched out its roster for the International Ice Hockey Federation Under-18 tournament in the spring over fears that players could test positive for meldonium. Russia used its U17 team in the tournament instead

The drug, which is typically used for heart conditions, is not approved for use in the United States. It increases blood flow, which improves exercise capacity by carrying more oxygen to the muscles. There is significant debate among doping experts over whether meldonium, also known as mildronate, actually enhances performance.