Petaluma vs. Hill's Prescription Diet i/d: Choosing a Food for Your Dog's Sensitive Stomach

By Caroline Buck, Co-founder of Petaluma

Digestion issues are a common reason pet parents start shopping for a new food for their pup. Hill's i/d is a prescription diet marketed for dogs with digestive trouble, and you can only buy it with your vet's approval.

Some vets also suggest an elimination diet, which means trying a new protein source or a hydrolyzed diet. During that process, many pet parents come across plant-based food and wonder whether it could be a good option for their dog.

Here is how i/d works and when a prescription digestive diet is the right call. We also look at where a gentle everyday food can fit, using Petaluma's three recipes as examples. If you are new to Petaluma, we make complete dog foods formulated by veterinary nutritionists, with plant proteins like soy and peanut in place of meat.

What Hill's i/d is and how it works

Hill's i/d Digestive Care is a therapeutic diet for dogs with digestive upsets. The dry chicken recipe lists 26.2% protein, 13.6% fat, and 2% crude fiber on a dry-matter basis. Dry-matter figures let you compare foods with different moisture levels. All three come from the Hill's product page.

Hill's describes i/d as highly digestible, with added electrolytes and B vitamins to replace what dogs lose during a digestive upset. It also contains ActivBiome+, a prebiotic fiber blend that Hill's says promotes healthy stool. The company calls i/d clinically proven to help manage digestive upsets.

Veterinary nutritionists use the same tools. A UC Davis guide by veterinary nutritionists Andrea Fascetti and Sean Delaney recommends a highly digestible diet with moderate to restricted fat after a stomach upset. They note that extra fat can make diarrhea worse when digestion is impaired.

i/d also has trade-offs. It needs a prescription, and its first ingredients are chicken, cracked pearled barley, brown rice, brewers rice, and whole grain corn. The ingredient list also includes chicken fat, chicken meal, and egg product, which matters for dogs that react to those proteins.

i/d Low Fat is a different food

Hill's also sells i/d Low Fat, with 7.4% fat on a dry-matter basis. Hill's says it helps lower blood fat levels. Dogs with a history of pancreatitis, which is inflammation of the pancreas, often need a low-fat diet like this one. Our pancreatitis guide explains why.

Petaluma's recipes are not low enough in fat for these dogs, so i/d Low Fat or a similar diet is the right choice for them.

Why i/d needs a prescription

i/d's protein, fat, and phosphorus all sit within the normal range for everyday adult food, as our guide to AAFCO nutrient profiles lays out. It is sold through vets because Hill's markets it to manage digestive disease. FDA policy expects diets with that purpose to be sold under a veterinarian's direction.

When does a dog need a prescription digestive diet?

Start with your vet when stomach trouble is new, severe, or keeps coming back. The Cornell Riney Canine Health Center says to call your vet for lethargy, vomiting that lasts more than 24 hours, a painful belly, or a fever. Blood in the vomit also calls for a visit.

Short-term upsets

For a one-time upset, vets often recommend a short break from food and then a bland, low-fat meal. The UC Davis guide then suggests a highly digestible diet such as i/d, with a gradual return to the usual food over several days.

Ongoing digestive problems

Diarrhea or vomiting that lasts for weeks is called chronic enteropathy, a long-term inflammation of the gut. Many of these dogs improve with a diet change alone. In one study reviewed in Clinician's Brief, 64% of dogs with chronic enteropathy responded to diet.

Those dogs often do best on a diet built around proteins they have not eaten before, or a hydrolyzed diet. The UC Davis guide notes that no diet is hypoallergenic by itself, since it depends on what a dog has eaten in the past. Our article on plant-based diets and IBD covers this in depth.

When to stay with i/d

• Pancreatitis or high blood fats: these dogs usually need i/d Low Fat or a similar low-fat diet.
• Active diarrhea or vomiting: a highly digestible therapeutic diet helps while your vet finds the cause.
• A dog doing well on i/d: if your dog eats it happily and the stools are steady, there is no reason to change.

Where Petaluma fits

All three Petaluma recipes are complete and balanced for adult dogs and formulated by veterinary nutritionists. Each gets its fiber from whole foods, and each measured above 92% protein digestibility in lab testing at the University of Bologna's veterinary school.

• Adult Baked Food: our oven-baked Roasted Peanut Butter & Sweet Potato Flavor is the everyday choice for most adult dogs. It has 17.2% fat and 17.4% total dietary fiber on a dry-matter basis.
• Senior Baked Food: our Baked Pumpkin & Peanut Butter Flavor is made for older dogs and includes pumpkin. Its fat is 14.9%, close to regular i/d's 13.6%, with 18.9% total dietary fiber.
• Whole Food Mixer: our dehydrated Whole Food Mixer is mixed with warm water, which suits dogs that prefer a softer meal. It has 14.3% fat, the most fiber of the three at 19.9%, and 94.7% protein digestibility.

None of the recipes contains chicken, beef, dairy, or egg. That can help dogs whose vet suspects a reaction to common animal proteins. All three contain peanut, and the Mixer also contains soy, so they only count as a new diet for dogs that have not eaten those before.

Each recipe's lab analysis and digestibility report is on our nutrition page, so you can bring the numbers to your vet.

Dogs they can suit

• Sensitive but healthy stomachs: dogs whose vet has ruled out disease and who do well on a fiber-rich food.
• Dogs moving off i/d: once your vet says the upset has resolved, any of our recipes can be the everyday food you step back to.
• Dogs that react to animal proteins: when your vet suspects chicken, beef, or egg and agrees a plant-based food is worth trying.

Petaluma's recipes are everyday foods for dogs without active disease. They have not been studied as treatments for digestive problems, and none is low enough in fat for pancreatitis. For a dog with active symptoms, start with your vet and a prescription diet.

If your dog eats a meat-based food now

Most dogs whose owners look for a gentler food are eating a chicken or beef recipe today. Dogs need specific nutrients, such as essential amino acids, rather than specific ingredients. A complete and balanced plant-based food supplies those nutrients from plants. Our article on whether dogs need meat walks through the research.

Go slowly with any new food, especially for a dog with a sensitive stomach. Mix a little of the new food into the old and increase it over several days, as the UC Davis guide suggests after an upset. Our transition guide has a step-by-step schedule. Samples of the Adult, Senior, and Mixer recipes let you see what your dog likes first.

Hill's i/d vs. Petaluma, side by side

These foods are built for different jobs. i/d manages active digestive upsets under a vet's care, and Petaluma's recipes are everyday foods for dogs whose vet has ruled out disease.

Hill's figures are from the i/d product page. Petaluma's figures are averages from third-party lab analyses and University of Bologna digestibility reports, all linked on our nutrition page. Prices were checked in November 2026 and change often.

Per calorie, our baked recipes cost a little less than i/d. The Mixer costs more as a premium dehydrated food. None of them needs a prescription.

Questions to ask your vet before switching

The best decision comes from what is behind your dog's symptoms. These questions help you get a clear answer at the next visit.

• What is causing the stomach trouble? A food reaction and pancreatitis call for very different diets.
• Does my dog need a low-fat diet? Ask whether fat should stay below a set level, and bring our lab analysis so your vet can compare.
• Should we try a diet trial? If a food reaction is likely, ask which proteins your dog has eaten before and how long the trial should last.
• When should we recheck? Agree on what improvement should look like and when to call if it does not come.

If you and your vet decide to switch, go slowly, as described in the section on switching above. Our guide to the best food for IBD and chronic diarrhea covers more options.

Frequently asked questions

Is there a non-prescription alternative to Hill's i/d?

For dogs with active vomiting or diarrhea, pancreatitis, or a suspected food reaction, start with your vet and a therapeutic diet. For dogs whose vet has ruled out disease, a complete food with moderate fat can work as an everyday option, in line with the UC Davis guide to digestive nutrition. Petaluma's three recipes measured 14.3% to 17.2% fat on a dry-matter basis and get their fiber from whole foods like pumpkin, oats, and sweet potato.

Why does Hill's i/d need a prescription?

i/d's protein, fat, and phosphorus sit within the normal range for adult dog food. It needs a prescription because Hill's markets it to manage digestive disease, and FDA policy expects diets like this to be sold under a veterinarian's direction. Retailers such as Chewy contact your vet to approve the order.

What is the difference between i/d and i/d Low Fat?

Regular i/d has 13.6% fat on a dry-matter basis and is made for general digestive upsets. i/d Low Fat has 7.4% fat, and Hill's says it helps lower blood fat levels. Dogs with a history of pancreatitis often need the low-fat version.

Is a plant-based food safe for a dog with a sensitive stomach?

Yes, when the food is complete and balanced and your vet has ruled out disease. Dogs need nutrients rather than specific ingredients, as our article on whether dogs need meat explains. Switch gradually over several days, and see our transition guide for a schedule.

Can I switch my dog from i/d to a regular food?

Usually yes, once your vet says the upset has resolved and your dog does not need a long-term therapeutic diet. The UC Davis guide suggests moving back to a regular food gradually over several days.

Does pumpkin help dogs with an upset stomach?

Pumpkin is a source of fiber, and vets have long used fiber for large bowel problems such as colitis, as the UC Davis guide notes. Responses vary, and too much fiber can cause constipation or diarrhea. Our article on fiber and pumpkin covers how to add it.

How digestible is Petaluma's food?

In lab testing at the University of Bologna's veterinary school, Petaluma's recipes measured 92.6% to 94.7% protein digestibility. Each recipe's digestibility report is on our nutrition page.

References

1. Hill's Pet Nutrition. Prescription Diet i/d Digestive Care Chicken Flavor dry dog food. Accessed November 2026. hillspet.com.
2. Hill's Pet Nutrition. Prescription Diet i/d Low Fat Digestive Care Chicken Flavor dry dog food. Accessed November 2026. hillspet.com.
3. Fascetti AJ, Delaney SJ. Nutritional management of gastrointestinal disease. UC Davis School of Veterinary Medicine. vetmed.ucdavis.edu.
4. Chandler M. Chronic enteropathies. Clinician's Brief. 2016. cliniciansbrief.com.
5. Cornell Richard P. Riney Canine Health Center. Vomiting. Accessed November 2026. vet.cornell.edu.
6. U.S. Food and Drug Administration. CPG Sec. 690.150: Labeling and marketing of dog and cat food diets intended to diagnose, cure, mitigate, treat, or prevent diseases. 2016. fda.gov.
7. Petaluma. Nutritional analyses and University of Bologna digestibility reports for Adult Baked Food, Senior Baked Food, and Whole Food Mixer. 2022 to 2026. feedpetaluma.com.
8. Chewy. Hill's Prescription Diet i/d Digestive Care Chicken Flavor dry dog food, 17.6 lb. Accessed November 2026. chewy.com.