Helping cats and dogs live their healthiest lives.
Sacred Birman kitten stood next to an adult Yorskhire Terrier in black and white.
Vet Products

Promotes digestive health and optimal stool quality with highly digestible proteins and prebiotics

Formulated to help manage GI health and common gastrointestinal sensitivities

Enriched with a blend of soluble and insoluble fibers for healthy transit through the GI tract

Supports urinary health with the exclusive S/O Index, which creates an environment unfavorable to crystal formation in the bladder

You’ve tried everything to help with your cat's GI issues, whether those are vomiting, diarrhea, or lack of appetite. And while bland homemade diets are often used for digestive upsets, your cat could be missing some key nutrients to help them fully recover. But with the help of your veterinarian and Royal Canin, there’s not just hope—there can be a true difference.

This high fiber cat food is specially formulated with a blend of soluble and insoluble fibers to aid with intestinal movement for your cat’s GI upsets. A combination of highly digestible proteins and prebiotics helps maintain the balance of good bacteria in the gut. A blend of dietary fibers supports healthy digestion for optimal stool quality. Omega-3 fatty acids, EPA and DHA, from fish oil help nourish and soothe the GI tract. And the exclusive S/O Index supports urinary health by creating an environment unfavorable to crystal formation in the bladder. Looking for a way to reward your cat? Royal Canin Gastrointestinal cat treats are just 1 calorie and made for your cat’s sensitive stomach.

Brewers rice, chicken by-product meal, chicken fat, corn, corn gluten meal, wheat gluten, psyllium seed husk, natural flavors, chicory, egg product, potassium chloride, fish oil, calcium sulfate, grain distillers dried yeast, fructooligosaccharides, DL-methionine, potassium phosphate, salt, vegetable oil, hydrolyzed yeast, choline chloride, taurine, vitamins [DL-alpha tocopherol acetate (source of vitamin E), L-ascorbyl-2-polyphosphate (source of vitamin C), niacin supplement, biotin, riboflavin supplement, D-calcium pantothenate, pyridoxine hydrochloride (vitamin B6), vitamin A acetate, thiamine mononitrate (vitamin B1), vitamin B12 supplement, folic acid, vitamin D3 supplement], L-lysine, marigold extract (Tagetes erecta L.), trace minerals [zinc proteinate, zinc oxide, ferrous sulfate, manganese proteinate, manganous oxide, copper sulfate, calcium iodate, sodium selenite, copper proteinate], rosemary extract, preserved with mixed tocopherols and citric acid.

Calorie Content

This diet contains 3687 kilocalories of metabolizable energy (ME) per kilogram or 361 kilocalories ME per cup on an as fed basis (calculated).

Crude Protein (min) 29.0%
Crude Fat (min) 13.0%
Crude Fiber (max) 4.7%
Moisture (max) 8.0%
Eicosapentaenoic Acid (EPA)* (min) 0.18%
Docosahexaenoic Acid (DHA)* (min) 0.08%

*Not recognized as an essential nutrient by the AAFCO Cat Food Nutrient Profiles.

Weight Tendency to become Overweight Ideal Weight
4.4 lb (2 kg) 1/4 cup (26 g) 3/8 cup (33 g)
5.5 lb (2.5 kg) 3/8 cup (31 g) 3/8 cup (38 g)
6.6 lb (3 kg) 3/8 cup (35 g) 1/2 cup (44 g)
7.7 lb (3.5 kg) 3/8 cup (39 g) 1/2 cup (49 g)
8.8 lb (4 kg) 1/2 cup (43 g) 1/2 cup (53 g)
9.9 lb (4.5 kg) 1/2 cup (46 g) 5/8 cup (58 g)
11.0 lb (5 kg) 1/2 cup (50 g) 5/8 cup (63 g)
13.2 lb (6 kg) 5/8 cup (57 g) 3/4 cup (71 g)
15.4 lb (7 kg) 5/8 cup (64 g) 7/8 cup (79 g)
17.6 lb (8 kg) 3/4 cup (70 g) 7/8 cup (87 g)
19.8 lb (9 kg) 3/4 cup (76 g) 1 cup (95 g)
22.0 lb (10 kg) 7/8 cup (82 g) 1 cup (102 g)

Royal Canin Veterinary Diet Feline Gastrointestinal Fiber Response Dry Cat Food

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Customer reviews

16 Aug 2019

Saved my cat’s life!!

My Ninja kitty was very sick with a hypomotility issue that eventually causes megacolon. It took a good 6 months of her being very sick to finally reach a diagnosis! I tried every medicine available and once I found this food and put her on it- her life changed! She gained all of the weight back that she lost and now feels so great! It’s amazing to have my cat back to normal, and all because of this food!
Royal Canin response
So great to hear that Ninja is doing to well!
phoebes owner
23 May 2019

Great food but bag too big

This has been a life saver for my cat, who has an extremely slow GI system. However, the bag is TOO BIG, as it apparently becomes bad tasting after about 2-3 months. My cat then stops eating it and I have to throw out half of a bag. I've tried freezing and vacuum sealing the food in smaller bags to try and preserve it, but it still becomes unpalatable. Please provide this product in a bag half the size of the 8.8 pounds. Other royal canin varieties come in smaller bags--so why not this one.
22 Apr 2019

works for a while

I dont like that this product contains by-product, Meat should always be the first ingredient, but instead does not include any. my cat will only eat this food if he has to. it works for his stools thats the only good thing i can say. and its expensive for a small bag.
01 Jan 2019

Great for older kitties

I have been using this product for about 2 years. Love the product. Don't like the fact that I can't get it in a 17 pound bag. Do you have any plans to make the product available in larger bags. Very expensive to buy multiple small bags.
Royal Canin response
I would be happy to make the suggestion for a larger bag!
28 Dec 2018


My himalayan Persian developed "mega colon" and came real close to dying. My vet got him cleaned out and now he is on this product along with Lactulose. So far so good and he has gained back much of the weight he lost when sick. The vet bills were extensive and this food isn't cheap but it saved his life!
11 Dec 2018

A life saver

I adopted a sibling pair of 1 yr old female cats, unbeknownst to me one of them had megacolon. It took several months to show symptoms, but after an emergency vet visit and surgical deobstipation my vet recommended RC fiber response. It's been 18 months and Freckles is doing wonderfully, so well in fact that I was able to wean her off her meds. All 4 of my cats now eat RC fiber response exclusively. My parents have a cat with hyperthyroidism and secondary IBS, he is now on RC fiber response and he has done amazing as well.
Royal Canin response
Wonderful to hear that they are all doing so well!
30 Nov 2018

Cured my cat!

My cat couldn’t stop throwing up, every single day. We tried all kinds of foods, pills, and supplements, until the vet finally recommended this one. It immediately cured him. He is so calm and happy now, it’s like his personality came back now that he finally feels better. Just one side note: your cat will poo SO MUCH while on this food, but the nice thing is that it doesn’t stink!
Kitty Snoble
10 Nov 2018

It works!

I was able to stop using lactulose with my kitty. Through the years i have used this diet with 3 different cats with success.
07 Nov 2018

Change in formula?

This food was pretty amazing. The only thing that helped my cat with his constipation problem. I also use it for my other cat since he has a history of urinary crystals. The only problem is that lately, they have had runny stools and what sounds like a lot of gas. Not sure if the formula was changes? They have been on this food for years and we never had this problem before.
05 Nov 2018

I am so grateful our vet recommended this product , it literally has saved my cat's life. We had tried so many products and many trips to the vet to help Tigger with his bowels always getting bound up.After using this product less than a week he was doing great and has not had a reaccurance of issues.