Rihanna has allegedly been warned by doctors to make some "serious lifestyle changes" or risk putting her health on the line.

The international superstar - who is famed for her party-hard antics - was forced to cancel tour dates in Baltimore and Boston recently after contracting laryngitis.

Medical experts have now reportedly warned the songstress to slow down her hectic schedule.

"Rihanna's illness was so severe that doctors warned it could take months for her to fully recover - there were worries that she'd have to cancel her entire tour," a source told British magazine Heat. "They've told her that she needs to make some serious lifestyle changes, or risk this happening again.

"This has given her a scare. But Rihanna knows it's partly self-inflicted. She loves to smoke, drink and stay up late. Her body was bound to need a break at some point. She's now on a mission to start looking after herself."

Rihanna's recent reunion with violent beau Chris Brown has caused a negative backlash, which is also said to have put the pop beauty under strain.

"Ri-Ri's received death threats, verbal attacks and has fallen out with some of her best friends, including Katy Perry. This has taken a huge emotional toll," the insider added.

Rihanna was admitted to hospital with suspected exhaustion and put on a drip during her world tour last year.