Purina Pro Plan Veterinary Diet HA Hydrolyzed is a prescription dry cat food formulated for cats with food allergies, food intolerance and related conditions. It's designed to be used under veterinary supervision as part of managing food sensitivities that manifest as stomach discomfort, severe itching or scratching.

The formula uses hydrolysed proteins — where the protein molecules are broken down into fragments small enough that they're less likely to trigger an allergic reaction. It also incorporates low-allergen carbohydrates to reduce the overall likelihood of reactions. This formula can be used for the nutritional management of cats with food-allergic gastroenteritis, food-allergic dermatitis, food intolerance, chronic non-specific diarrhoea or vomiting, pancreatitis and inflammatory bowel disease. It should only be used on veterinary advice.

Hydrolysed-protein diets are often the only solution for cats with genuine food allergies, and elimination trials using this kind of food are the gold standard diagnostic approach. Pro Plan's HA formula is widely used in Australian clinics and has a strong track record for palatability — an important consideration for cats who have to stay on it long-term.