A spokesman for a Montreal hospital says Janet Jackson was released just two hours after she arrived.
But it's still unclear why she was admitted.
W&W Public Relations says the 42-year-old singer became "suddenly ill" and was taken to Royal Victoria Hospital on Monday night shortly before her scheduled concert in Montreal, which was canceled.
Representaives for Jackson are not elaborating on her condition, simply saying that she is "recuperating."
Jackson's shows in Boston and Philadelphia on Wednesday and Thursday have been postponed. She is due to resume her tour in Greensboro, N.C. on Saturday.
Jackson is on her first North American tour in seven years.