(Cover) - EN Showbiz - Rihanna has reportedly been warned by doctors to slow down or face more illnesses.

The Barbadian singer was forced to cancel a show in Sweden earlier this week after she was rushed to hospital with flu-like symptoms. She was put on a drip and told she would not be well enough to take to the stage.

The star is currently completing her Loud world tour, and has also been working on new material when off stage. That, combined with her love of partying, means she hasn't been resting that much.

"Rihanna is running on empty but she's still been going out drinking and living it up," a source told British newspaper The Sun.

"She doesn't have any down time where she can completely relax. She spends most of her time in the studio, on stage or in clubs.

"Doctors are worried she's overdoing it. She needs to take some time off. Otherwise she'll be vulnerable to more illness."

Those close to the 23-year-old have already shown their support. Hip-hop star Jay-Z and music mogul L.A. Reid were quick to send her flowers when they heard she was unwell.

Rihanna released a statement apologising to fans when she had to call off the Sweden show. She also posted a picture of the drip in her arm on Twitter.

The star is known for her intense work ethic. Since 2005 she has released five records, with her sixth called Talk That Talk due out on November 18. (C) Cover Media