Hello fellow cat lovers!
I've talked about my beloved pet, the most affectionate cat in the world, in a previous post here.
How we developed an allergy to proteinMy cat is soon to be 9 years old, and he's still as loved and carefree as ever. However, as he's gotten older, his coronavirus, which he contracted from the breeder, hasn't gone away and still gives him trouble from time to time. We've been regularly doing check-ups with him, but he'd get diarrhea and vomiting, so we'd just treat him for the virus, only for it to come back again. A vet warned us that letting the coronavirus run chronic could lead to a viral peritonitis in cats. They said that with a good immune system, the virus might eventually leave the body, but that wasn't our case. In the end, due to chronic inflammation from the coronavirus, my cat's digestive system was damaged, and he developed an intolerance to protein. We tried different vets and clinics, and I'm only sharing the final outcome with you now, as to what we've learned so far.
So, we found out about his protein intolerance.
Protein intolerance or allergy in cats is an abnormal immune reaction to specific components of their food (usually chicken, beef, fish, or dairy products). It manifests as intense itching, hair loss, skin lesions, vomiting, or diarrhea. Treatment involves switching to a hypoallergenic diet or removing the allergen under a vet's supervision.
I've noticed that the symptoms of food intolerance in my cat manifested in a pretty unique way. At first, we thought it was just a skin issue, but it turned out to be related to the digestive system. My cat would get diarrhea and vomiting about 1-2 times a week, and even after recovering from COVID-19, the symptoms persisted. The weird thing was that the vomiting would only happen after eating. According to the vet, the stomach lining was irritated, and when food would enter the stomach, it would cause pain and vomiting. But, as I mentioned earlier, the typical symptoms of food intolerance are usually more apparent in the form of dermatitis, which wasn't the case with my cat.
Symptoms of food protein intolerance
Food allergies often resemble dermatitis, and symptoms can develop at any age:
Skin reactions (main symptom): intense itching, redness, miliary dermatitis (crusts), swelling around the eyes, self-trauma due to excessive grooming.Localization: head, neck, belly, groin.GI disturbances: chronic vomiting, diarrhea, bloating.Respiratory signs: coughing, sneezing (less common).To determine the intolerance, we were recommended an elimination diet (by two veterinarians at different clinics). However, if your pet has more pronounced allergy symptoms, switching to a new food might not be enough, and you may need to consider additional measures.
What to do about food protein intolerance
Switch to a specialized diet: Hypoallergenic (hydrolyzed) foods, where protein is broken down to a form that's not recognized by the immune system, or diets with a new protein source (e.g., duck, rabbit).Exclude mixed feeding: Completely remove treats and human food during diagnosis.Consult a vet: To address secondary skin infections and itching, medications may be prescribed.Finding the right food
I'll be honest, it wasn't easy with a picky cat. As of January 2026, in Russia, there are only two pet food companies that use pea protein. In all other companies, if you read the ingredient list carefully, there's still animal protein, even if it says hypoallergenic. And that's not going to work if you need to exclude protein completely. We spent months experimenting, trying to find a food that worked for our cat. We ruled out all conserved foods, because they still contain protein, even in hypoallergenic ones.
So, we were left with those two companies that use pea protein.
My cat didn't take to the cheaper one, and no matter how many times I tried to offer it to him, he would give me a disapproving look and walk away.
That left us with only one option: Purina Proplan Hypoallergenic.
PRO PLAN Hypoallergenic – A dry, complete, and balanced diet for kittens and adult cats with allergies. The food is recommended for reducing sensitivity to ingredients and nutrients, based on specially selected protein and carbohydrate sources. The formula is free from grains and has a lower fat content, enriched with high-quality protein sources and easily digestible carbohydrates, providing optimal digestion and supporting skin and coat health. The food contains prebiotics that promote a balance of gut bacteria, as well as Omega-3 and Omega-6 fatty acids for a healthy coat and skin. PRO PLAN Hypoallergenic is a tasty and nutritious choice for cats prone to allergies and food sensitivities.
Unfortunately, it's currently not being manufactured in Russia, so it's available on marketplaces, but it's shipped from Belarus or Kazakhstan. The price is quite steep, with a 1.3kg pack costing between 2800-3500 rubles. But we didn't have many options, and our cat needed to exclude protein ASAP.
First ImpressionsI've got to say, the packaging left a great impression. Like all high-end foods, it's sealed in a tight pack with a zipper, making it super easy to use.
On the back, there's a multilingual instruction sheet. The Russian version is even stuck on there separately.
Looking at the ingredients, it's clear they've got plant-based protein sources. Animal-derived protein is way down the list, and it's even in the form of a hydrolyzed protein source.
Hydrolyzed animal-derived protein is a protein product obtained by enzymatic or acidic hydrolysis of meat by-products into small peptides and amino acids. It's easily digestible, acts as a natural flavor enhancer to improve the taste of feed (attractant), and is a hypoallergenic component.
Inside, I found little light beige pellets that looked and smelled just like regular food - nothing to suggest this was a soy-based food.
Kitty's First Impressions
My cat took to this food right away, no negative reaction at all. He even came to it, and ate it eagerly. And let me tell you, he's always been a picky eater, only eating about 50-70% of his daily ration. But with this food, he devours the whole thing, 100% of his daily ration, every time.
My ImpressionsI've been feeding my cat this Purina Proplan Hypoallergenic food for about 8 months now. The vets' initial suspicion that my cat had a protein allergy was confirmed - he was clearly allergic to the animal-derived protein in his old food. We've finally seen the end of the periodic diarrhea and vomiting. My cat is now a happy, well-fed kitty who's much more relaxed about mealtimes. If he was starving before, he'd go begging at night - and we'd try to fatten him up with cans, only for him to get diarrhea or vomit again. But now, he's always satisfied, and he's even put on a stable 300 grams. The vet says it's because the food is finally being absorbed by his body.
Drawbacks
One thing I've noticed is that my cat gets constipated on this food. It's not a deal-breaker, but it's definitely a drawback. We've learned to deal with it by making sure he drinks enough water - it turns out cats can be pretty forgetful about that! We've scattered water bowls, bottles, and even a few jugs around the house. Every three months or so, we give him a small dose of Dufalac to get things moving again. The vet thinks it's partly due to his age, but we've learned to manage it.
ConclusionI think Purina Proplan Hypoallergenic is a great, high-quality product that delivers on its promises. If you need to completely eliminate animal-derived protein from your cat's diet, this food is a great choice. And I'm impressed that my cat doesn't seem to mind the soy-based ingredients - he's not rejecting the food at all.
I'm thoroughly recommending Purina Proplan Hypoallergenic. Wishing you and your furry friends all the best health and happiness.