Hi lisa, poor woofer. My dog is gluten intolerant (as I m sure everyone on AB must know by now, sorry!), and for a few months he was ill as you described. It might be worth trying him on a gluten free food, if it is dry dog food you normally feed him. Otherwise, especially if it's only periodic, I would probably leave his diet be: too much change will probably make it worse, not better. I am sure your vet could probably help out too if it's starting to affect him in his everyday life. x