Royal Canin has developed a method that makes it possible to determine the S/O Index of a food. The S/O Index is based on the acidity (pH) of urine, urine volume and the concentration of various components in urine that can form stones. Thanks to the low S/O Index, Royal Canin Urinary S/O Small Dog can dissolve struvite stones and prevent both struvite and calcium oxalate stones.

Royal Canin Urinary S/O Small Dog has an adapted kibble size, which are easy to eat. Small dogs are more prone to tartar formation. Therefore, Urinary S/O Small Dog contains sodium polyphosphate to reduce tartar formation. Royal Canin Urinary S/O Small Dog is suitable for dogs up to 10 kg. For dogs heavier than 10 kg, there is the Royal Canin Urinary S/O dog.