The incident occurred 45 seconds into the third period of Toronto's 4-2 win Wednesday night. Lupul received a two-minute minor penalty for an illegal check when he hit Hedman in the head after the defenceman passed the puck in the neutral zone.
It was just Lupul's second game back after missing 25 contests with a broken arm.
He scored three goals in those two games.
Lupul will forfeit US$45,945.94 in salary. He has no history of supplemental discipline in his nine-year career.
Hedman briefly left the game but returned and suffered no apparent injury.