FYI, Tylan is poisonous to people. I have a bunch of it left over from Beta.
Please do a search in this section for "Basenji without spunk". This thread was about my basenji girl that passed away. I put in a lot of information about medications and what they were used for. It may give you some insight to what the meds are doing to your basenji.
My girl had IPSID and another disease that were difficult to identify until it was too late. Hopefully some of that information in that thread may give you more insight about IPSID and IBS and other diseases.
The vet recommended to me right away, a change in diet to Natural Balance Duck and Potatoe soft food. You can do a search online to read about that food. It is for sensitive stomachs and has no grain, no wheat, no rice, no soy and no preservatives. It was the only think I could get Beta to eat when she couldnt hold anything down.
It actually turned out to be such a good food that I have my other two basenjis eating the dry version of it now. There are several different varieties to choose from.
I purchase the food from a feed store and it was the only thing that Beta (my girl) could eat that she could poop in somewhat of a solid form vs. throwing it up.
Tylan is used for ulcers as well as Carafate. If the stomach has an ulcer the carafate sticks to it and works on healing it by coating it as well.
Have you ruled out giardia?
Have you done a scope to see if it is upper intestine or lower intestine. Is there any throwing up?
They put Beta on Prednisone when they couldnt do anything else. It is an anti inflamatory and works great, but can mask other problems.
From what I have read, the best thing to do with a sensitive GI track is to use sensitive foods and gently change the food every 4 months to avoid your basenji becoming allergic to the foods. That is what was described to me about IPSID. My vet said IBS and IPSID are commonly confused if your vet doesnt have experience with Basenjis.
You are not alone and you are doing great! If you have any questions you are welcome to PM me or post them here. This group was so supportive to me as my girl became ill.