The visitors took the lead just after the half hour mark, with Charlie Kelman left with space in the box to place a header from close-range past Harry Tyrer.
Steve Bruce’s side had multiple chances to pull themselves level, including a miss of the season contender from Ashley Fletcher.
After bringing the ball down well, and taking it past Josh Keeley in the Orient goal, the striker lifted his shot over the crossbar.
Meanwhile, either side of the break, both Rob Apter and Niall Ennis were denied by superb saves from the visiting goalkeeper.
On the hour mark, the Seasiders pulled themselves level, as Sonny Carey produced some quick footwork to continue his scoring run.
The home celebrations didn’t last long, with Orient quickly edging themselves back in front – courtesy of Kelman once again.
Further chances came Blackpool’s way, with Ennis and substitute Jake Beesley also offering their own contributions for miss of the day.
Here’s how the Seasiders performed:
7. Rob Apter- 6
Rob Apter had a huge chance at the end of first half, but was denied by a superb save from Josh Keeley at close-range. Photo: CameraSport - Lee Parker
8. Albie Morgan- 6
The Blackpool midfield were unable to take control of a chaotic contest. Photo: CameraSport - Lee Parker
9. Lee Evans- 6
Lee Evans was at fault for not making the right decisions in certain situations. Photo: CameraSport - Alex Dodd
10. Sonny Carey- 7
Sonny Carey provided a rare clinical moment for the Seasiders, with his quick feet leading to his goal. Photo: CameraSport - Lee Parker
11. Ashley Fletcher- 5
Ashley Fletcher produced a contender for miss of the season. After showing good control to take the ball around the keeper, the forward lifted his shot over the crossbar of the empty goal. The 29-year-old worked hard throughout, but the miss will be the main thing remembered from his performance. Photo: CameraSport - Alex Dodd
12. Niall Ennis- 5
Niall Ennis had his own miss of the season contender, with the forward hitting the bar from close-range. The Stoke City loanee was also among those to be denied by a Josh Keeley save. Photo: CameraSport - Lee Parker