Purina Pro Plan Veterinary Diet UR Urinary St/Ox is a prescription dry cat food formulated for adult cats prone to lower urinary tract conditions. Scientifically developed to meet the dietary needs of cats at risk of both struvite and calcium oxalate crystal formation, it's used under veterinary supervision as a long-term management option.

The formula is designed to help manage the dissolution of struvite stones while also reducing the risk of calcium oxalate formation — the two most common types of urinary crystals seen in cats. It achieves this through careful mineral balance and by influencing urinary pH, creating an environment less favourable to crystal formation. Suitable for adult cats with a history of urinary issues or for cats identified as at elevated risk by their vet. Like all veterinary diets, it should only be used on a vet's recommendation.

Feline Lower Urinary Tract Disease (FLUTD) is one of the most common reasons cats end up at the vet, and diet is central to managing it long-term. Pro Plan's UR formula is widely prescribed in Australian practices precisely because it addresses both major crystal types rather than just one.