Thanks for the answers to my questions.
Unfortunately, I'm not equipped to take phone calls and hope that this format is acceptable to you. My apologies for the inconvenience.
I essentially agree with the list of possible explanations for his initial symptoms although sometimes it's not always possible to know exactly the cause of gastrointestinal signs without additional diagnostics.
I often dispense Metronidazole for my patients when they develop diarrhea which typically helps to firm up the stools; however, having said that, diarrhea is listed as one of the adverse side effects for some patients.
Clavamox is notorious for causing looser stool issues so either one or both of these drugs could be causing the problem he's having.
It's going to be difficult to know if he's having a drug reaction until or unless the drugs he's currently taking are discontinued. If he's otherwise acting fine, then I'm unclear as to why he's continuing to be medicated.
If he does have IBD, then you're correct that it would take a biopsy to diagnose which many owners are understandably reluctant to do especially for such a young cat.
1. However, rather than a pred trial at this time (which I'll sometimes do even without a specific diagnosis), I'd change his diet to something more hypoallergenic. Diet plays a huge role in causing intestinal inflammation and often just such a change can help the patient.....although for some additional drugs are needed.
Feeding grain free may help in some cases but other diets to consider would be Z/D (from your vet), or Natural Ba***** *****mited Ingredient Diets, Nature's Variety Instincts line, Evo duck or venison, Nature's Variety Frozen Raw Medallions (I recommend that they be zapped in the microwave for 10-15 seconds on each side).
Sometimes this is a trial and error process---finding the food that your cat will eat as well as one that helps with the problem.
2. I'd also continue probiotics which, hopefully, he's still taking.
Additional supplements which may help these cats include:
3. l-glutamine 500mg/day crush in food which is available at health food stores or online.
2. NuCat Senior which is a supplement which contains anti-oxidants.
3. Vitamin D3 1,000 IU day.. but not calcitriol. This amount of Vit D3 is not dangerous to cats
I'm not certain that he does have IBD as a cause for his symptoms especially if he ingests all kinds of things which could also cause gastrointestinal irritation. But, it sounds to me as if he may be over medicated at this point. It may be time to take a step back and reevaluate the situation....although a change in diet as I mentioned above may be something to consider since it clearly won't be harmful.
I hope this helps. Deb