The 31-year-old was in action for his country against Venezuela on Friday night.
Brazil led 1-0 going into the closing stages via Gabriel Magalhaes' effort, but were pegged back by Eduard Bello's late leveller.
Following the 1-1 draw in Cuiaba, Neymar and his team-mates trudged off the pitch having fallen behind Argentina in the World Cup qualifying table.
As he was about to enter the tunnel, however, Neymar was struck on the head by a box of popcorn, thrown by an irate fan.
The Al-Hilal ace immediately looked up into the stands to try and identify the culprit, subsequently hurling angry words as he pointed to an individual.