Yes, we tried domperidone. We tried it out of desperation b/c Hailey was said to have DGE (though she was never formally tested for it) and was refluxing a lot. Our GI hoped that if her stomach emptied more than she wouldn’t reflux as much and might poop more. It didn’t do anything for the reflux or the pooping, and did nothing to improve the feeding aversion.
I’m not sure what your doctor is hoping the domperidone will do to correct the feeding aversion. I can’t remember all of your history, so forgive me if you’ve already tried this, but we found that the first step was really to get the reflux pain under control- so a good dose of a stable form of PPI given correctly. Next step is to try a formula switch to one of the hypo or elemental formulas or to do elimination diet.
If that doesn’t help things and you want to go the testing route, you can ask for a feeding evaluation, and a swallowing study/modified barium swallow (to be differentiated from an upper GI).
Good luck. I hope things improve.