Sounds gross, but every single opiate addict knows ALL about it.
I recall about 10-12 years ago here on Bluelight there was a thread where some guy used afork from his aunty's kitchen drawer to pull out his poop cos there was no other way he could think of to get it out, and was then debating whether he should wash it and put it back in the kitchen drawer :D
Does anyone else remember that??? Surely I'm not the only one.
Anyway, to answer your question, when I was using, I took HEAPS and heaps of fibre supplement capsules (psyllium husk) and drank heaps of water every day to help me poop. I was still constipated every day but I could at least get it out....without using a fork