Help, my rabbit eating but not pooping?

Make sure his butt isn't plugged on the outside. You could even try soaking it in some water. Get him some fiber-rich food and lots of water.

i had the same problem with my rabbit mant times before. if he feels stiff and swollen in his abdomen then he is constipated and is a very common problem in rabbits and is very uncomfortable for them... my rabbits vet gave me a small (needleless) serenge and a tube of stuff called cat lax (its a cat laxative), he said that its harmless to rabbits, it wont hurt them. you can find it in the pet section at walmart or farm supply stores or petco. fill the serenge half way with the laxative, hold your rabbit securely, slip the serenge in his mouth and squirt it in twice a day until you notice that he has passed a significantly larger amount of stool. if you cant find cat lax, then go to the grocery store and buy a can of UNsweetened pumpkin pie filling, but make sure its NOT the sweetened kind. some rabbits eat it willingly but you may have to load it into the serenge and administer it yourself. the pumpkin really loosens their bowels. i would try this because your rabbit is probably very uncomfortable and its such a common problem among rabbits, a laxative wouldnt hurt him.

Make sure it isn't all just sticking to him. He has maybe not eaten the right amount of his cecotrypes so his digestive track is a bit dodgy. I advise you to give him some greens, I find my rabbits poop a lot eating them.