oh my gosh...bad info on clumping litter :(

Are you sure thats its just IBS causing his pooey problem?? Sometimes just the antibiotics themselves can upset tender tummies. I've been battling with diarrhea and tummy trouble with my kitty for like 8 months or something. I also had her on metronidazole for 2 weeks. She's finally better now, but i believe the medicine was also making her sick. She vomitted several times when i first started her on it. Because i had so many health battles with her since i got her, i started using Yesterday's News litter with her. Since it's paper based, i figured it would be better for sensitive kitties, plus i have 5 rodents and so they all get YN and its just easier. If you want to switch your cats litter, its usually best to do it gradually and mix with old litter. I'm lucky my cat isnt picky about that sort of thing, but i know a lot of them are. Also could be food allergies adding to the IBS problem....i had to deal with that in mine too, since she has a sensitive tummy. You could try offering a Chamomile tea to help with tummy upsets.