Rihanna canceled a show in Sweden after being hospitalized for severe exhaustion caused by a bad case of the flu.

Kristofer Akesson, a spokesman for concert sponsor Live Nation, told The Associated Press that tour organizers took Rihanna to a doctor when she felt sick on Monday, and the doctor concluded that Rihanna was not capable of carrying out the concert.

The Disturbia singer tweeted a photo of herself with an IV drip in her arm, along with the message Sorry Malmo!!! #LOUDtour.

I am sorry to everyone who was coming out to my show in Malmo, Sweden, she said in a statement posted on her Web site. I was so excited to perform for you all. It would have been a great time... so much better than being sick with the flu, ugh! I'm really disappointed I couldn't be there.

Rihanna was scheduled to perform in Malmo Monday night as part of the Live Nation tour. A replacement date has not been announced yet, but Live Nation said in a statement that the show would be rescheduled and that all tickets purchased for the original date would be honored on the new date. Refunds will also be available for people who cannot make the new date.

According to Akesson, Rihanna is now out of the hospital and in Stockholm, where she is expected to perform as scheduled Tuesday night.