I’ve done a ton of searching for nonprescription hydrolyzed protein dog foods, and I have only ever seen three on the market:
1. The Wholehearted hydrolyzed salmon and pea version you mention, which is my usual go-to.
2. A pretty expensive version from a company called Square Pet: https://www.amazon.com/SquarePet-Veterinarian-Formulated-Hydrolyzed-30813/dp/B0891FW98S/
3. A remarkably inexpensive version from a company called Diamond Care: https://www.amazon.com/DIAMOND-CARE-Grain-Free-Formulation-Hydrolyzed/dp/B01M2ZK9JI/
