Lab puppy digestive issues

My 6 month old lab puppy has been having dietary problems. We started him on Blue Puppy and around the 4 month mark he became ill from some allergy medicine. His stomach has not fully recovered. Our vet had us switch food to a prescription digestive health food (Hills Prescription Diet® i/d) with a lower protein level for 14 days and his diarrhea was fixed. However, the moment we reintroduced his new food (slowly) his stomach issues reared back up.

Any recommendations on a food that I should switch too more permanently?

Thanks

My dog is currently on Science Diet for sensitive stomach. Maybe that will be good for your dog? He also has food allergy like yours. My dog had some bad reaction from the blue brand treats so I never tried their dry food.
Good luck to you!

My shepherd had the same thing happen after being on antibiotics numerous times then all of a sudden diarrhea episodes had to fast her 12 yo 24 hrs then put her on a beef and rice diet for a few days but every time I put her back on kibble e diarrhea started again it got so bad she started having some blood from straining to her back to vet again said she had colitis put her on one of the vets low fat kibble diets she had worse diarrhea so I looked into homemade food and she has been a lot better least I know what is in it, I also got her a supplement to put in her diet to make sure it was balanced, maybe think about trying the homemade food, to many antibiotics can wreck there gut. Good luck