Former American tennis star Jennifer Capriati says Maria Sharapova should be stripped of her titles after failing a doping test at this year's Australian Open.

Sharapova tested positive to the banned substance Mildronate, also known as meldonium, which the 28-year-old says she uses to counter a magnesium deficiency and a family history of diabetes.

The substance, which she has been taking since 2006, was added to WADA's banned list on January 1 this year. All players were informed of the updated WADA banned list for 2016 in December, but Sharapova admitted she "didn't read" the letter.

Meldonium has been found to increase blood flow which improves exercise capacity in athletes.

"In my opinion of its all true every title should be stripped. This is other people's lives as well," Capriati wrote on Twitter.

https://twitter.com/JenCapriati/status/706986855087153152?ref_src=twsrc^tfw

Capriati was also unconvinced about Sharapova's justification for taking the drug in which the banned substance was found.

"What's the point of someone taking a heart medicine that helps your heart recover faster unless you have a heart condition? Is thataccurate?"

Former World No.1 and three-time Grand Slam champion Capriati, had her own career spectacularly cut short after she was arrested for possession of marijuana.

https://twitter.com/JenCapriati/status/706954883279273984