How to Do an Elimination Diet for Dogs (And What to Feed During One)

June 30, 2026

If your dog has been dealing with chronic itching, ear infections, or digestive trouble, you've likely already tried switching foods without relief. An elimination diet is the gold standard diagnostic tool for identifying the specific ingredient behind those symptoms.

An elimination diet is a strict, controlled feeding trial using a single protein your dog has never eaten, lasting a minimum of eight weeks, followed by a careful reintroduction phase. This guide covers every step, including what to feed, what to avoid, and what to do once you find the trigger.

How to Do an Elimination Diet for Dogs: Step-by-Step

A successful elimination diet follows four essential phases: selecting the right food, identifying which ingredient triggers your dog's symptoms, and confirming the diet's effectiveness.

Step 1: Choose a Novel Protein

A novel protein is one your dog has never eaten before. Because the immune system hasn't encountered it, there's no existing allergic response to trigger.

What counts as "novel" depends entirely on your dog's feeding history. While you might wonder, “Is chicken or beef better for dogs?”, these proteins only qualify for a trial if your dog has never consumed them.

Share a complete list of every food, treat, and table scrap with your veterinarian to guide this decision. When diet history is unclear or too broad, a hypoallergenic dog food for allergies utilizing hydrolyzed proteins offers an alternative.

Information about therapeutic dog food should be considered in conjunction with veterinary guidance as part of a supervised diagnostic plan. Research has shown that some over-the-counter limited-ingredient dog food options contain undeclared proteins from manufacturing cross-contamination¹. One study found that 65% of 29 OTC commercial dog foods tested contained undeclared chicken DNA.

Step 2: Remove All Other Foods & Treats

Strict compliance determines whether the diet trial succeeds. Every bite outside the elimination diet can compromise results.

The following must be eliminated completely:

Treats, chews, and rawhides of any kind
Flavored medications including heartworm chews and flavored antibiotics
Table scraps and human food even in small amounts
Supplements containing animal-derived ingredients
Flavored toothpaste used during tooth brushing
Other pets' food or access to litter boxes

Use small pieces of the elimination diet itself as dog treats for training. Ask your veterinarian about switching flavored medications to unflavored or topical alternatives.

Make sure every family member, dog walker, and caregiver understands the trial requirements.

Step 3: Run the Trial Period (8–12 Weeks)

Gastrointestinal symptoms like diarrhea or gas often improve within the first few weeks. Symptoms of dog skin allergies and conditions, including itching and ear infections, typically require the full eight-to-twelve-week window to resolve.

According to the Merck Veterinary Manual, a minimum of 10 weeks might be required to identify 95% of food-allergic patients². Keep a daily log tracking itch level, skin condition, ear health, and stool quality.

This record helps evaluate results and guides the reintroduction phase. Ending the diet trial too early is a common mistake that misses a significant number of food-allergic dogs.

Step 4: Reintroduce Foods One at a Time

Once symptoms have improved, the challenge phase begins. Reintroduce one previously eliminated ingredient at a time, allowing up to 2 weeks per food while watching for symptom flare-ups.

If symptoms return after adding an ingredient, that food is confirmed as an allergen. Stop it immediately and return to the elimination diet until symptoms resolve, then test another ingredient.

Research from the University of Bristol confirms that common triggers of cutaneous adverse food reactions include beef, dairy and chicken in dogs³, which is why these proteins are often logical starting points for challenges. Other common food allergens include wheat and soy.

Best Proteins to Use During an Elimination Diet

When determining the best protein for dogs during an elimination diet, novel options commonly used include the following:

Venison
Duck
Rabbit
Kangaroo
Bison

These protein sources appear less frequently in commercial pet food, making them "novel" for most dogs. They're not inherently less allergenic.

Ingredient transparency matters during a trial. Foods with vague labels like "animal derivatives" or hidden fillers introduce unknown variables that can compromise results.

During a trial, review fresh dog food options by ingredient list to confirm they match the veterinarian-selected elimination diet criteria. Grain-free diets are not the same as elimination diets. Most food allergies in dogs are triggered by animal proteins, not grains.

What to Do After You Find the Trigger Food

Long-term management means strict avoidance of the confirmed allergen across all food, treats, supplements, and medications. Read and compare dog food labels carefully, choosing foods with transparent ingredient lists. The CDC recommends looking for the words "complete and balanced⁴" on product labels when buying food for your dog's main diet.

Many dogs with food allergies benefit from an anti-inflammatory diet for dogs to support skin and gut recovery. If you're evaluating long-term feeding options after a dog food elimination diet, look for foods with clearly identified ingredients and protein sources. Darwin's offers minimally processed raw meals made with human-quality ingredients and transparent ingredient labeling. Check out our products today!

Sources: