The 22-year-old Italian was taken to hospital in South Wales after becoming ill during the half-time break in the Black Cats' 2-2 Barclays Premier League draw at the Cardiff City Stadium.
Manager Gus Poyet later revealed Borini, who had been suffering from a virus in the run-up to the game, had been released from hospital, but would not fly back to the north-east with the rest of his team-mates on Saturday night.
However, a club spokesman said on Sunday: "Fabio is feeling much better and will return to Wearside today."