Miley Cyrus won't be twerking onstage come Friday.

The 21-year-old was supposed to resume her highly anticipated Bangerz tour in Europe, but her health has once again sidelined her—forcing her to reschedule her Amsterdam show, originally scheduled for May 2.

“Cyrus is continuing to recover from the severe allergic reaction she suffered on April 15. After a period of improvement, Cyrus’ symptoms have returned and doctors will not permit her to travel,” an official statement reads.

It continues, "Cyrus must remain under doctor's care at this time. The London date at O2 Arena will proceed as planned on May 6."

Miley's camp claimed she was hospitalized after suffering a severe allergic medication to antibiotics (Cephalexin) she was taking to help cure a cold with flu-like symptoms.

Miley Cyrus Forced to Cancel Tour Dates After Hospitalization

But Dr. Michael Zimring, an internist with Mercy Medical Center in Baltimore who has never treated Miley, tells Life & Style that Cephalexin is not an antiobiotic that is usually associated with strong adverse reactions.

"I've never seen a serious, prolonged reaction in my 35 years of practicing medicine," Dr. Zimring tells the mag, adding it's even rare for patients to be kept overnight. (Miley's rep initially said she needed five to 27 days of treatment.)

As Life & Style reports in this week's issue, friends close to the star believe her hard partying is to blame.

“She has really overdone it,” one of her pals tells Life & Style. “All the partying, drugs and drinking doesn’t mix well.”

miley cyrus

Miley opened up about her scary ordeal to Ryan Seacrest earlier this week and said, "I'm doing good, I’m doing much better.

“I had basically been poisoning myself with something I didn’t know I was really scary allergic to,” she admitted. “It was scary.”

E! was the first to break the news of the show’s cancelation.

For more on Miley, pick up the new issue of Life & Style, on stands now.