In an Instagram post on Saturday, the pop star said her throat and head were "still experiencing so much pain" and it was difficult to breathe during a show. She said she had been battling the disease since her concert in London last month.
"I just really don't know what's going on with my body right now and I have to figure it out," Grande said.
Although canceling the show is "the last thing I would ever want to do," Grande writes, fans should accept the post as "gentle heads up" in case she can't "make the show happen." on Sunday.