(CNN) -- Miley Cyrus suffered "a severe allergic reaction to antibiotics" and has been hospitalized, her rep told CNN Tuesday.
Her Tuesday night "Bangerz" tour concert at the Sprint Center in Kansas City, Missouri, has been canceled, according to a statement from the arena.
"Cyrus has been hospitalized for a severe allergic reaction to antibiotics and has been placed on medical rest by her doctors," the statement said. "She will not be able to perform as scheduled."
The 21-year-old singer was not too ill to tweet from her Kansas City hospital bed, though.
Mr. Octopussy & some amazing Drs are taking good care of me 🌈 pic.twitter.com/7FJFxYa7M5— Miley Ray Cyrus (@MileyCyrus) April 15, 2014
"Kansas I promise Im as (heartbroken) as you are. I wanted so badly 2 b there 2night. Not being with yall makes me feel s--ttier than I already do," she wrote in a Twitter message to fans Tuesday afternoon.
"Mr. Octopussy & some amazing Drs are taking good care of me," Cyrus wrote in tweet that included a photo of her in a hospital bed wearing a gown. She was holding a green octopus toy in front of her face.
Cyrus fell ill with the flu earlier this month, causing the cancellation of a concert in Charlotte, North Carolina.
CNN's Carolyn Sung and Matthew Stucker contributed to this report.
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