Relative Supersaturation (RSS) methodology predicts the crystallization potential of urine. RSS is used to develop diets for dogs prone to both struvite and oxalate urolithiasis.

Hydrolyzed protein, composed of low molecular weight peptides, is highly digestible and minimizes signs associated with food sensitivities.

Specially formulated to assist in the management of struvite and calcium oxalate crystals and stones and adverse food reactions in the canine patient.

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Labrador Retriever adult sitting with its owner outdoors

Brewers rice, hydrolyzed soy protein, chicken fat, natural flavors, dried chicory root, salt, vegetable oil, pea fiber, fish oil, calcium sulfate, potassium chloride, sodium silico aluminate, monocalcium phosphate, fructooligosaccharides, taurine, vitamins [DL-alpha tocopherol acetate (source of vitamin E), niacin supplement, D-calcium pantothenate, biotin, pyridoxine hydrochloride (vitamin B6), riboflavin supplement, thiamine mononitrate (vitamin B1), vitamin A acetate, vitamin B12 supplement, folic acid], choline chloride, DL-methionine, N-butyric acid, trace minerals [zinc proteinate, zinc oxide, manganese proteinate, manganous oxide, copper sulfate, ferrous sulfate, sodium selenite, copper proteinate, calcium iodate], GLA safflower oil, marigold extract (Tagetes erecta L.), rosemary extract, preserved with mixed tocopherols and citric acid.

Calorie Content

This diet contains 3592 kilocalories of metabolizable energy (ME) per kilogram or 327 kilocalories ME per cup on an as fed basis (calculated).

Crude Protein (min)18.0%
Crude Fat (min)13.0%
Crude Fiber (max)3.9%
Moisture (max)10.0%
Calcium (max)0.73%
Phosphorus (max)0.7%
Magnesium (max)0.07%.
Body Weight Tendency to be Overweight Ideal Weight
8.8 lb (4 kg) 3/4 cup (71 g) 7/8 cup (82 g)
17.6 lb (8 kg) 1 3/8 cups (120 g) 1 1/2 cups (138 g)
22.0 lb (10 kg) 1 1/2 cups (141 g) 1 3/4 cups (164 g)
26.4 lb (12 kg) 1 3/4 cups (162 g) 2 1/8 cups (188 g)
30.9 lb (14 kg) 2 cups (181 g) 2 3/8 cups (210 g)
35.3 lb (16 kg) 2 1/4 cups (201g) 2 5/8 cups (233 g)
39.7 lb (18 kg) 2 3/8 cups (220 g) 2 3/4 cups (254 g)
44.1 lb (20 kg) 2 5/8 cups (238 g) 3 cups (275 g)
48.5 lb (22 kg) 2 3/4 cups (255 g) 3 1/4 cups (295 g)
52.9 lb (24 kg) 3 cups (273 g) 3 1/2 cups (315 g)
57.3 lb (26 kg) 3 1/8 cups (289 g) 3 5/8 cups (335 g)
61.7 lb (28 kg) 3 3/8 cups (306 g) 3 7/8 cups (355 g)
66.1 lb (30 kg) 3 1/2 cups (322 g) 4 1/8 cups (373 g)
77.2 lb (35 kg) 4 cups (361 g) 4 5/8 cups (418 g)
88.2 lb (40 kg) 4 3/8 cups (400 g) 5 1/8 cups (463 g)
110.2 lb (50 kg) 5 1/4 cups (473 g) 6 cups (548 g)
Royal Canin Veterinary Diet Canine Urinary SO + Hydrolyzed Protein Dry Dog Food

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Customer reviews

Christina199
02 Dec 2023

Bonus-no more blotchy skin issues

My vet recommended I try this because my dog avoids drinking water, her urine output is minimal and could lead to issues. A very unexpected bonus was that her consistently itchy and blotchy skin completely cleared up, presumably due to the hydrolized protein.
Steph G
29 Mar 2023

Very hard to get, works well.

This is basically the only food my dog can eat to prevent urine crystals and severe allergic reactions, including yeast infections in her ears, BUT WE CANNOT FIND IT ANYMORE!! My pretty girl is suffering….
GRAMMY 1
17 Mar 2023

My dog only eats it because she has to

My standard poodle has been on this food type for years and it has gotten so expensive I’m not sure what I’m going to do if I can’t afford it any longer !
W2022
31 Jul 2022

Worst decision ever

My 17 year old shih tzu on a regular basis uses Hidrolized Protein food. When I switched to the Hidrolized Protein with SO index (because regular Hidrolized protein was not available) she likes it but it brought up so many side effects. She’s super thirsty, constantly drinking water and peeing. She barely sleeps, walking around all day like disoriented, crying silently. I hace notice that she’s even more blind than was before because she is now bumping on everything in the house. It’s just horrible to see her acting so bizarre. Im changing her food for good today and going back to the Hidrolized Protein that she used to eat.
parkca
01 Jun 2022

Portia Loves This Dog Food

Portia had a urinary problem we found by accident at a young age. The Vet recommended putting Portia on the Royal Canin Urinary SO dry dog food. She was around 2 years old. She is now 12 1/2 years old and never has had a urinary problem.
Dj1021
01 Jun 2022

I was facing chronic bladder issues with my two dogs. Nothing seemed to work. My vet suggested I try Royal Canin Urinary SO dry dog food. I am happy to report this food has made all the difference. No crystals, no UTI!
Bon15
31 May 2022

Tired of taste

My dog used to eat with no problem. Now she’s tired of the taste
Dog Momma
19 Oct 2021

Please make snacks to complement this diet.

This food has been great for Sergeant Major's dietary, urinary, and skin allergies. But he really wants a snack :-( . Are there no snacks to complement this diet? That would be great!
Royal Canin response
Its a great suggestion!
kimmy13
20 Jun 2021

Love the formula!

My dog needs the SO diet and we started her with the hydrolyzed protein for her allergies. I love that there is a combo of the two to help with this. Since starting her on it she hasn't been licking unless to clean herself, the saliva staining is almost all gone, and she likes the different food from her siblings! Strong smell to me, but she loves it!
03 Mar 2021

Constantly Out of Stock

Ask your vet for an alternative because this is about the 5th time we have had a "backorder" of more than a month and had to scramble all over town or online trying to find a place that still has any in stock. The manufacturer offers no information on status or help. Serious production issues and whoever is in charge of production and supply should seek other employment.