ROYAL CANIN VETERINARY DIET Adult Urinary SO Moderate Calorie Dry Cat Food, 6.6-lb bag -

Royal Canin Veterinary Diet Adult Urinary SO Moderate Calorie Dry Cat Food

By Royal Canin Veterinary Diet
Rated 4.69 out of 5 stars
Veterinary Diet Item

$54.99Chewy Price
$52.24Autoship Price
(Save an extra 5%)

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  • Save 5% on all future Autoship orders
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This item requires vet authorization.

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About This Item


  • A veterinary-exclusive dry cat food for cats prone to weight gain with urinary health concerns.
  • Helps dissolve pure struvite stones and helps prevent calcium oxalate stones.
  • Moderate calorie content for ideal weight maintenance.
  • Lowers the risk of crystal formation using RSS methodology for bladder health.
  • Supports urinary health with an exclusive S/O Index, and creates an environment unfavorable to crystal formation in the bladder.

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Nutritional Information

Feeding Instructions


Play Video: Learn More About Royal Canin Veterinary Diet From Our Team of Experts
Learn More About Royal Canin Veterinary Diet From Our Team of Experts

About Royal Canin Urinary Health for Cats

Worried About Your Cat’s Urinary Health?

Your veterinarian is the expert on your cat’s health, so you should always consult with this trusted advisor to find the best urinary health solutions for your pet. Royal Canin works closely with veterinarians to develop cat formulas that help support urinary tract and bladder health.

How Can Nutrition Help?

Your veterinarian may recommend a Royal Canin Urinary cat food formula for your cat. These special formulations can:

Dilute Urine

This helps your cat urinate more often, which can help minimize time for stones to form.

Lower RSS

RSS methodology predicts urine crystallization and is used to develop diets that reduce the risk of stone formation.

Maintain Balance

A precise mineral balance can also help prevent stones from forming.

Set Up Autoship for Consistent Delivery

Last-minute dietary changes can sometimes upset your pet's stomach. Set your Royal Canin pet food order to Autoship to keep feeding on track and avoid unwanted disruptions.

About Royal Canin

What sets Royal Canin apart is their close collaboration with veterinarians. Through these professional partnerships, they strive to learn everything they can about pet health, including how different formulas perform for different breeds, sizes, lifestyles and therapeutic conditions. Ongoing research and development allows Royal Canin to keep providing the precise nutrition cats need for a range of medical conditions.

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Questions & Answers

30 Customer Questions

Can another cat (without special diet) eat this?
Answer by ChewyJan 25, 2018
Since this is a prescription food formulated to meet specific diet restrictions from known health issues, this food should not be fed to any other animal than the one prescribed due to the restriction of specific nutrients. Prescription diets can be detrimental to an otherwise healthy pet if that pet doesn't have the ailment for which the food is designed.

My 2 cats have been eating the regular Royal Canin urinary cat food for several years now, they love it but at least every other day they throw it up. Will switching to this food help with that? Thank you!
Answer by ChewyOct 25, 2017
We encourage pet parents to consult with a veterinarian to make sure this is the best fit for your pet and their current treatment plan.

How many cups are in the 6.6 lb bag?
Answer by ChewyJan 15, 2019
The 3.3-pound bag has about 13 cups of food, the 6.6-pound bag has about 26 cups of food, and there are about 70 cups of food in a 17.6-pound bag.

What kind of animal protein is this food made from?
Answer by ChewyJan 03, 2018
The protein in this formula is from chicken.

ReviewsWrite a Review

Rated 4.69 out of 5 stars
1016 Ratings
Would recommend to a friend

1016 Customer Reviews

Always consult a veterinarian about your pet’s health needs. Customer reviews should not be used as medical advice.
Rated 5 out of 5 stars
By Caro on May 31, 2023

Prescribed by vet

One of our cats was blocked and after a few days with the vet, came home with a new diet plan. Purchasing this prescribed food seemed a bit daunting ($$$) but he doesn’t eat a ton of it. I think because it is a higher quality food than what we were giving before that he doesn’t need as much. Purchasing online was easy (chewy reached out the the vet for script). I like the delivery vs carting a giant bag from store to car, car to house. Last thing, I like the “ziplock” at the top of the bag to help keep it as fresh as possible & I didn’t need to buy a secondary container.

Rated 5 out of 5 stars
By AJ on Apr 25, 2023

Great food, Mr. Moo loved it

We adopted Mr. Moo when he was 10 y.o. he always had crystals in his urine, so vet prescribed Urinary SO. He loved it! We had him on half wet food and half dry (through an auto feeder) because he loved the dry food so much, but we didnt want to onky feed him dry food. He would run from across the house whenever his auto feeder started rumbling. We had Moo for 7 years. Unfortunately after this last order, we lost 17 y.o. Moobear to large stones in his urinary tract, but the vet said this food was why he was so healthy for 7 years after we adopted him, and why he did well for so long, despite already showing signs of urinary issues at age 10. We're grateful for 7 great years with our handsome boy. And Chewy's customer service has been outstanding.

Rated 5 out of 5 stars
By Rachel on Apr 19, 2023

Working great and cat loves it!

As a former vet tech, I was only familiar with Hills urinary diet. My cat had PU surgery after they couldnt unblock him and we were suggested to use Royal. Royal is intended for long-term diets and mostly works by increasing salt intake to promote drinking. While not completely ideal (as our cat has a heart murmur), we decided to use his regular wet and change his dry to this. He hated the Royal wet, but seems to really enjoy the dry! He’s drinking more than he used to which is helping him urinate 2-3 times a day rather than 1-2 (his previous normal). I wish these diets came in other protein variants, but we’re very happy so far

Rated 5 out of 5 stars
By Amy on Apr 27, 2023

This food has been a lifesaver!

My cat was prescribed this food by our vet, after having multiple bouts of painful and bloody urination. She is also on the canned version. She loves both types of food! Since starting this diet she has only had one instance of blood in her urine in the past several years, whereas before it was very frequent. This food is a bit expensive, but not nearly as expensive as it was to take her to the vet every few weeks! It's worth every penny as it has improved her health tremendously.

Rated 5 out of 5 stars
By eddie on May 29, 2023

royal canin urinary so prescibed dry cat food

my cat loves it and it has helped him a lot and eating dry food gets him drinking more water which is good so happy with this product been using it for going on 2 years now

Rated 3 out of 5 stars
By Janell on Apr 25, 2023

Royal Canin urinary formula dry food

One of my cats eats this with no problem. The other will eat it as a last resort but throws it up before it is digested. Not sure what the problem is. He will barely eat the canned version and seems to keep it down.

Rated 5 out of 5 stars
By KittyLove on Feb 25, 2023

Best food for urinary crystals

My vet recommended this food for our cat that has urinary crystals. Within a week, our cat was feeling better and no crying after using the litter box. She needs the moderate calorie food as well because she tends to gain weight very easily. The taste is apparently very good also, since my other kitty tries to sneak in and gobble it up. So happy that it is now back in stock at Chewy. We tried another brand of prescription diet food when this was out of stock, and it did not work as well as the Royal Canin. Thank you Chewy!!

Rated 4 out of 5 stars
By Simon on Apr 12, 2023

Saved his life

Royal Canin’s food has saved Simon’s life! He developed bladder crystals that almost took his life but because of the Veterinary diet Urinary SO food he is living his best life. My only complaint is that I can’t get the SO treats anymore.

Rated 5 out of 5 stars
By Debdarling on May 26, 2023

Rx Required But Quick Service

I appreciate the speediness Chewy & my vet processed this ordered. And, it was so easy. And, my cat still likes this food.

Rated 2 out of 5 stars
By Leslie on Apr 16, 2023

Urinary SO recent shipment

Urinary SO recent shipment is "flaking" leaving dust at the bottom of the bowls. I have purchased the Royal Canin Urinary SO multiple times and this is the first time there has been an issue.