The American leg of Miley Cyrus' tour is now officially over, thanks to an "extreme allergic reaction" to an antibiotic.

Her representative released a statement Friday indicating that "all remaining U.S. dates on the Miley Cyrus 'Bangerz' tour have been postponed." That means that shows scheduled next week for Philadelphia, at Foxwoods casino in Connecticut, and on Long Island, New York are officially off -- at least for now.

The announcement isn't entirely unexpected: Her representative said Thursday that the entertainer could need a lot more time to recover from the ailment that landed her in a Kansas City hospital last week.

"Sick of waking up to needles," the 21-year-old Cyrus tweeted Friday. "#goingthruit."

The singer canceled a show in Charlotte, North Carolina, last week because of what was reported to be a flu-like illness. But the severity of her condition wasn't fully known until this week, when she canceled performances in Kansas City and St. Louis. In a statement, her camp explained that Cyrus got a sinus infection while in North Carolina, then "was prescribed the antibiotic Cephalexin, which she has now suffered an extreme allergic reaction to."

"This type of extreme reaction can last from five to 27 days in these types of cases," the statement said.

"She will remain hospitalized and is under a doctor's care until we see some improvement in her condition and is asking for your compassion and privacy at this time. Miley is devastated about missing shows and possibly disappointing her fans."

But it appears Cyrus won't be off the stage for long. Her representative said Friday "the European leg of the tour will proceed as planned," starting with a May 2 date in Amsterdam. This summer, she should be back partying in the USA, as she intoned in one of her best-known hits.

A slew of new shows, running between August 1 and August 14, were announced Friday to replace recently canceled ones. Those dates include two additional shows in Pittsburgh and Chicago. Miley: Post-Disney, post-Liam and stronger than ever Miley's miserable day

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