Can't say in general but had this prob with mine. (Dental/stasis bun) It turned out that he had a mild overgrowth of the wrong bacteria in his caecum (dybiosis) & they were causing his colon to slow down. He was trying to get it moving again by eating pure waste fiber - wood pulp. He also had squidgy poohs.
The final answer was a short course of Ranitidine (Zantac). [metaclopramide - maxolon only gets the top end of the gut moving - the problem is the caecum/colon bottom end]
Fiberplex paste has fiber & probiotic & is the best to get the gut flora back in balance. But I gather Eric is a bit fiesty too. Can get probiotic to add to water.
Diet - nothing with starch or sugar at all. Keep low on "nutrient" - greens & veg, & pellets. Extra high on hay & fibrous leaves from shrubs & trees.
Just have a feeling from reading several of your recent posts that Eric has a similar prob. Everything crossed for you both.
xxx Judy & Thumper xxx
Beau gets thru a couple of pages of the yellow pages, a bit of an Argos catalogue and at least one kitchen roll a day and seems to be none the worse - touchwood! My mum said "that can't be healthy" when she saw him eating the yellow pages, but I couldn't bare to take it off him, it's his favourite!