The Italian - on loan from Liverpool - was substituted at the interval during the 2-2 draw at the Cardiff City Stadium, reportedly after collapsing in the dressing room.
He was subsequently taken to hospital and kept in overnight for observation.
A statement on Sunderland's official website read: "Fabio Borini is heading back to the north east after being affected by illness during yesterday's game at Cardiff.
"He was taken to hospital as a precaution and was kept in overnight before returning to Wearside on Sunday morning."
In Borini's absence, Sunderland came from behind to snatch a hard-fought draw, with Jack Colback scoring in the 95th minute after Steven Fletcher had reduced the deficit.
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