Stefani sent out a tweet that said: "I am so sorry, but I am still not feeling well & will be unable to perform my #JustAGirlVegas show Saturday, February 8 at @ZapposTheater at @PHVegas."
She added that she's doing her best to make sure she can perform for her shows running Feb. 12-22.
"I am doing everything I can to get well & plan to be back on stage for my shows February 12 – 22. Thank u for all of the well wishes. Hope to see you back in Vegas soon. gx #onlyhuman #imsorry #loveuguys," she tweeted.