We use unscented, clumping litter with pan liners and remove the clumps and stool twice a day, with a complete change every few days.

Our three cats have no problems with this so far. Litter made from ground corncobs might also be good for your cat. We used that for the rabbit we used to have, and liked it.

I would look first at her diet before I'd say litter is the main problem. She'll feel better for awhile after the cortizone and antibiotic shot but that's a short term fix.

Also take note of where she sleeps and where she spends a lot of her time. Many household products & cleaners can cause skin irritation in our pets and if you're using any on her bedding or where she sleeps, that could also be a allergic reactions.

Thanks both of you for your helpful responses...guess it will be a trial and error thing trying to figure out what the problem is...thanks again...Mary