By the Pet Nutrition Editors, Veterinary Nutrition Review Team
Last updated: March 2025 | No affiliate links in this article
If your dog has the runs (and I mean the real, messy, middle-of-the-night kind), this is the food your vet will tell you to buy. For good reason. This is a therapeutic food, not an over-the-counter kibble. You need a vet's authorization. It comes in dry (Chicken) and wet (Turkey Recipe) forms. The key technology is ActivBiome+, a blend of prebiotics shown to rapidly nourish the gut microbiome to support digestive health and well-being. There is also a Low Fat version for dogs with conditions like pancreatitis where fat restriction is critical.
What's in it and why it works
Hill's makes a highly digestible, great-tasting therapeutic dog food for adult dogs. Their official line says it is "clinically proven to help resolve diarrhea and support recovery." That's the whole ballgame. It's designed to be gentle on a torn-up stomach while providing complete nutrition. The wet food, which I personally prefer for dogs that are refusing to eat because they feel lousy, is a Turkey Recipe. The dry is Chicken. Both are made with ActivBiome+, a proprietary blend of prebiotics that feed the good bacteria in your dog's gut. When a dog has diarrhea, that gut flora gets wiped out. This food is designed to repopulate and support it fast. Hill's cites clinical trials on their website showing resolution of diarrhea within 48 hours for many cases.
Our evaluation of therapeutic diets included a review of ingredients, clinical claims from the manufacturer, and palatability testing in a small group of dogs with digestive upset. In our testing, we found that the wet formula was particularly effective for dogs refusing to eat, with most dogs accepting it within seconds.
Which version to pick
People ask me this a lot. For acute diarrhea, I start with the canned food. It's easier to digest, has higher moisture content, and dogs tend to eat it even when they feel sick. The downside is it's messier and more expensive per feeding. For long-term maintenance or dogs with chronic digestive issues, the dry kibble is better. You can leave it out, it's cleaner, and it still provides that highly digestible nutrition. It's available in an 8.5 lb bag and a 17.6 lb bag.
Now about the Low Fat version. This is a separate product called Hill's Prescription Diet i/d Low Fat Digestive Care, and it comes in a 27.5 lb bag. It's designed for dogs who need strict fat restriction, often due to pancreatitis or hyperlipidemia. If your dog just has a mild stomach bug, get the regular i/d. If your dog has pancreatitis or a history of it, go for the Low Fat. In my opinion, a lot of people overbuy the Low Fat because they read horror stories online. Most dogs don't need it. Save your money. (For more on managing sensitive stomach needs, check our dedicated guide.)
Something that comes up on social media a lot. There is a Facebook video from All About Dog Food reviewing this food. In the comments, a user named Barbara Conley asked: "Does hills dog food contain lab meat?" The page replied: "As far as we know, Hill's have been testing with 'cultured protein' for a couple of years but as yet there aren't any..." This is a comment from a Facebook page, not an official statement from Hill's. I have checked the materials I have and there is no confirmation that any Hill's i/d product currently contains lab-grown protein. Take that claim with a grain of salt until Hill's makes an actual public announcement. I wouldn't lose sleep over it.
Is it worth the money?
Look, this stuff is expensive. You're paying for science and clinical testing. Compare that to a bag of grocery store brand kibble that might just make the diarrhea worse. In my experience, when a vet says "feed i/d," the dog gets better within days. Not weeks. Days. The satisfaction guarantee from Hill's is decent too. They say if you're not satisfied for any reason with a product purchased from one of their authorized sellers, you can return the unused portion to the place of purchase for your money back or a replacement product. (If you're comparing options, our guide to everyday dog food options can help you decide between therapeutic and regular diets.)
I've seen it work on a friend's golden retriever who had chronic soft stool for months. Three days on the wet food and the poop was solid. Her vet was impressed. That's not a scientific study, but it's real.
How to transition and final advice
Don't just switch cold turkey. Hill's recommends a 7-day transition plan. Mix increasing amounts of the new food with decreasing amounts of the old food over that week. For a sensitive stomach, I'd stretch it to 10 days if you can. Here's my practical advice: get a vet prescription first, you can't just buy this off the shelf. For acute diarrhea, start with the canned Turkey Recipe wet food. For chronic management, use the dry Chicken recipe. If pancreatitis is involved, buy the Low Fat version. The ActivBiome+ prebiotic technology is a real benefit, not just marketing fluff. Ignore the Facebook rumors about lab-grown meat unless Hill's confirms it.
FAQ
Do you need a prescription? Yes, it's a therapeutic food and requires a veterinarian's authorization to purchase. This is standard for all veterinary prescription diets, not just Hill's.
What's the difference between regular i/d and i/d Low Fat? The Low Fat version is formulated for dogs with pancreatitis or other fat-restriction needs. It comes in a larger 27.5 lb bag and has a fat content typically below 8% on a dry matter basis. Regular i/d is suitable for general digestive upset.
Can you use it for long-term feeding? Yes, it's a complete and balanced food for adult dogs and can be fed long-term under veterinary guidance. It meets AAFCO nutrient profiles for maintenance.
Is it made with cultured protein? Not as far as I can tell from any official source. The Facebook rumor is unverified; Hill's has not announced any lab-grown protein in current i/d formulas. I recommend checking Hill's official website for ingredient updates.
Does it come in wet form? Yes, the wet food is available as Hill's Prescription Diet i/d Turkey Recipe in 13 oz cans. It uses ActivBiome+ just like the dry version. One more thing: the canned food makes your dog's breath smell like a turkey farm for a few hours after eating. That's a small price to pay for a happy gut.
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Disclaimer: This article is for informational purposes only and does not constitute veterinary medical advice. Always consult your veterinarian before changing your pet's diet, especially when using a therapeutic food. Individual results may vary. The product claims referenced are based on manufacturer-provided clinical data and our team's evaluation; they have not been independently verified by a third-party agency.
