What else can my dogs bloated stomach be, on meds for a week and little difference.

[DebbiePip]

Hi, I really need help!! My dog has a bloated stomach, and has been on 1st an antibiotic , then now, a stronger antibiotic plus a low dose steroid. The vet did an X-ray and tried to drain fluid out of the abdomen. There wasn't any fluid to get out(which was good he said) and the X-ray just showed enlarged organs, nothing else. They did a CBC and everything was normal. He (the dog) acts mostly normal, plays, runs, walks ... does both #1 and #2. He has been a bit irritable (of course) and will eat, but it takes MANY tries of putting food up and down until he eats it. I always have him dehydrated food you add water to, now I'm adding some rice as well to make it more bland. Vet thinks it's done form of IBS. Well, he has 2 days left on his antibiotic, and his stomach has gone down A LITTLE, but it's still bloated. IM SO WORRIED with everything I've read, I'm going out of my mind! I take him back in 2 days for a recheck, and would like some insight on what else could it be????? HELP!!
Debbie