The Hills star needed stitches after a little fun tim...
He tells PeoplePets.com, "(We) were just playing with one his new toys and the rope slipped out of my mouth when Rainbow tugged. (It was) very innocent, but it definitely hurt... Sometimes accidents happen.
"I'll think twice about sticking the toy in my mouth next time."
Spencer Pratt has since 'tweeted' photos of his swollen mouth online.