The Argentine striker was on a boat trip with friends in Capri when he slipped on a rock, requiring eight stitches to his jaw and two to his eyebrow
The Argentine, who made his debut for the Partenopei debut following his big-money move from Real Madrid on Sunday, slipped on rocks and injured his jaw while in the Marina Piccola in Capri.
He was promptly rushed to hospital where he received a number of stitches - eight to his jaw and two to his eyebrow.
The 25-year-old remained conscious the whole time, was soon discharged and was greeted by two club medics at the hotel where he has lived since arriving at the San Paolo.
Doctors are assessing his situation ahead of Saturday's match against Chievo, but he is expected at the club's training ground as usual on Tuesday.
Higuain started Napoli's 3-0 win over Bologna on Sunday, playing 84 minutes before being replaced by youngster Josip Radosevic.