Chris Kunitz, Tyler Kennedy, Steve Sullivan and Evgeni Malkin all scored for the Penguins within a 7:25 span to turn a one-goal deficit into a 4-1 lead.
Pittsburgh chased Ottawa starting goaltender Craig Anderson before the first period was halfway gone.
Sidney Crosby assisted on three of the goals -- including a beautiful cross-ice feed to Kunitz following a shot fake -- as the Penguins bounced back from a loss to St. Louis on Wednesday in style.
"I think we wanted to start better than we did last game," Crosby said.
"It was just a matter of doing that. They scored early but we knew there was a lot of time left and we could get back into the game. Everyone responded well, and that carried over for the next two periods."
Penguins Score Four Goals In First 10 Minutes