The widow of John Lennon was hospitalised at Mount Sinai Roosevelt Hospital in New York on Friday with flu-like symptoms, according to her publicist Elliot Mintz.
Son Sean tweeted on Saturday that his 83-year-old mother had now been released and the reason for her hospitalisation was "just the flu".
"Thanks again for everyone's concern. She's home and running about as usual. Just the flu in the end. I may go get a flu shot now..." He later shared a photo of his mother backstage at a Black Sabbath gig at Madison Square Garden, with the caption, "Celebrating healthy mum with a little Sabbath!!!"
When news broke of Yoko's hospital visit, Elliot was quick to play down rumours that the artist and activist had suffered anything serious. He said: "It was never ever a stroke. She was suffering extreme flu-like symptoms. Her doctor thought it would be a good idea to go to a local hospital to be checked out.
"She went to hospital. She is being checked out. The information that she has been given is that in all likelihood she will be out tomorrow (Saturday)."
Sean also let fans know that his mum was doing OK.