The Fleetwood Mac crooner was advised to lay low after she was recently stricken with pneumonia and the flu, E! News has confirmed.
So what does this mean for fans expecting to see her perform live in New York this week?
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They'll just have to wait.
Nicks' doctor gave her strict orders to "stay in bed and not fly" until she recovers, causing her to cancel her Tuesday appearances on Today and Good Day NY and a Wednesday star-studded event at Webster Hall to promote the release of her upcoming album, In Your Dreams.
"I want to apologize to all my fans and hope that we can reschedule, and of course I hope you love the new album," Nicks said in a statement. "It's for you."
Fans can still catch the gypsy queen Tuesday, however, when her highly anticipated Glee episode airs.
In Your Dreams, Nicks' first solo album in 10 years, hits stores Tuesday.