Royal Canin HP Dog Food: Complete Guide to Hydrolyzed Protein Diets

What Is Royal Canin HP Dog Food and Why Do Vets Prescribe It?

Royal Canin HP (Hydrolyzed Protein) is a veterinary-exclusive therapeutic diet designed for dogs with food allergies, inflammatory bowel disease (IBD), and adverse food reactions. The "HP" stands for hydrolyzed protein — meaning the protein molecules have been enzymatically broken down into fragments so small (typically under 1 kilodalton) that the immune system cannot recognize them as allergens.

This diet sits in Royal Canin's Veterinary Diet lineup alongside the Ultamino and Selected Protein lines, but HP is often the first-line elimination diet veterinarians reach for because of its extremely low molecular weight protein profile. According to the Merck Veterinary Manual, hydrolyzed diets are considered the gold standard for diagnosing adverse food reactions because they bypass the immune triggering mechanism entirely.

Royal Canin HP comes in two primary formats:

• Royal Canin Veterinary Diet Hydrolyzed Protein HP Dry — kibble format, available in 13.2 lb bags
• Royal Canin Veterinary Diet Hydrolyzed Protein HP Canned — wet food format, sold in 13.5 oz cans (cases of 12)

Both require a veterinary prescription. You cannot purchase them over the counter or through standard pet food retailers without vet authorization.

Nutritional Profile: What's Actually in Royal Canin HP?

Understanding the guaranteed analysis helps you see why this diet works — and where supplementation may be needed long-term.

Key observations: The protein level (18% as-fed) is moderate — lower than most maintenance diets, which typically run 22-30%. This is intentional. Hydrolyzed diets prioritize molecular weight reduction over protein quantity. The fat content (8% as-fed) is also on the lower end, which suits dogs with concurrent GI sensitivity but may not meet the energy demands of highly active dogs without increased volume.

AAFCO Statement: Royal Canin HP is formulated to meet the nutritional levels established by AAFCO Dog Food Nutrient Profiles for adult maintenance. It is not approved for growth (puppies) or gestation/lactation. If your puppy needs an elimination diet trial, your vet will likely recommend a different formulation.

Who Benefits from a Hydrolyzed Protein Diet?

Hydrolyzed diets like Royal Canin HP serve specific clinical purposes. They are not general-purpose "premium" foods — they are therapeutic tools.

Primary Indications

• Food allergy diagnosis (elimination diet trial): The 8-12 week trial period where HP is the sole food source to determine if symptoms resolve
• Confirmed adverse food reactions: Long-term management once food allergy is diagnosed
• Inflammatory bowel disease (IBD): Reducing antigenic load on an inflamed GI tract
• Chronic otitis externa: When ear infections are suspected to have a food allergy component
• Chronic pruritus (itching): Non-seasonal itching that doesn't respond to flea/tick control alone

Conditions Where HP May Not Be the Best Choice

• Environmental allergies (atopic dermatitis): If your dog's itching is driven by pollen, dust mites, or mold rather than food, a hydrolyzed diet won't resolve symptoms — though it's still used diagnostically to rule food out
• Pancreatitis: The 8% fat content is relatively low, but dogs with severe pancreatitis may need an even lower-fat therapeutic diet
• Kidney disease: The protein level is moderate, but renal diets have different phosphorus and protein management goals — your vet will choose accordingly

How Much Royal Canin HP Should You Feed Your Dog?

Feeding amounts depend on your dog's ideal body weight (not current weight if overweight), activity level, and metabolic rate. The caloric density of HP dry food is approximately 315 kcal per cup.

Adjustment factors to consider:

• Neutered/spayed dogs: Reduce by 10-15% from normal activity — altered dogs have a slower metabolic rate
• Senior dogs (7+ years): Reduce by 10-20% unless they remain highly active
• Weight loss protocol: Feed for ideal weight (not current weight), then reduce by an additional 10%
• Concurrent medications: Steroids (prednisone) increase appetite and can cause weight gain — monitor closely

Top Alternatives to Royal Canin HP: Hydrolyzed and Limited-Ingredient Options

While Royal Canin HP is effective for many dogs, it's not the only hydrolyzed or hypoallergenic diet available. Here are the most common veterinary-recommended alternatives, with pricing current to early 2026.

What Ingredients Should You Avoid During an Elimination Diet Trial?

The most common mistake owners make during a hydrolyzed diet trial is accidental exposure to allergens through treats, flavored medications, or table scraps. According to a study published in the Journal of the American Veterinary Medical Association, even small amounts of intact protein can trigger a relapse in sensitized dogs.

Reading Pet Food Labels: What to Look For

When evaluating any commercial dog food — therapeutic or maintenance — check these elements:

• AAFCO statement: Must read "formulated to meet the nutritional levels established by the AAFCO Dog Food Nutrient Profiles" for the appropriate life stage. Without this statement, the food has not been nutritionally validated.
• Ingredient order: Ingredients are listed by weight before processing. The first ingredient should be a named protein source (or in HP's case, hydrolyzed soy protein).
• Named fat sources: Look for "chicken fat," "sunflower oil," or "fish oil" rather than generic "animal fat"
• Guaranteed analysis: Minimum protein, minimum fat, maximum fiber, maximum moisture — these four values are required by law
• Caloric statement: kcal/kg and kcal per cup or can — essential for calculating portions

Can You Feed a Homemade Diet Instead of Royal Canin HP?

Technically yes, but the risks are substantial and the logistics are demanding. A homemade elimination diet requires a single novel protein source and a single novel carbohydrate, formulated to meet all of your dog's micronutrient requirements.

Typical Homemade Elimination Diet Framework

A veterinary nutritionist might formulate something like:

• Protein: Boiled rabbit, alligator, or horse meat (3 oz per 10 lb body weight per day)
• Carbohydrate: Boiled sweet potato or quinoa (1/2 cup per 10 lb body weight per day)
• Supplements: Calcium carbonate (to balance the phosphorus in meat), vitamin E, zinc, B-complex, fish oil (if approved), and a balanced mineral mix

Cost comparison: A homemade elimination diet typically costs $8-15 per day for a 40 lb dog (depending on the novel protein source), compared to $2.50-4.00 per day for Royal Canin HP dry food. The homemade route is significantly more expensive and time-intensive.

Transition Protocol: Switching to Royal Canin HP Over 7-10 Days

Even though HP is designed for sensitive GI tracts, an abrupt switch can still cause loose stools or appetite disruption. Follow this graduated transition schedule:

Important transition notes:

• Palatability: Hydrolyzed diets often taste different from standard kibble. If your dog refuses to eat, try warming the food slightly (to body temperature, ~100°F / 38°C), adding warm water to dry kibble, or mixing in the canned HP variety for flavor
• GI upset: Mild softening of stool in days 1-5 is normal. Watery diarrhea lasting more than 48 hours warrants a vet call — your dog may need a slower transition or a different formulation
• Don't rush: The 8-12 week elimination trial clock does NOT start until your dog is eating 100% HP. Any accidental protein exposure resets the clock

Supplement Guidance: What to Add and When

While Royal Canin HP is AAFCO-complete for adult maintenance, certain clinical scenarios benefit from targeted supplementation:

What NOT to supplement during the trial:

• Any protein-based supplement (bone broth powder, collagen, amino acid blends)
• Flavored joint supplements (many contain chicken or beef liver for palatability)
• Herbal supplements with unknown protein cross-reactivity

Monitoring Success: How to Know If Royal Canin HP Is Working

The elimination diet trial lasts 8-12 weeks. Here's what to track and when to expect improvement:

Symptom Timeline

• Weeks 1-2: GI symptoms (diarrhea, vomiting, gas) often improve first — within 7-14 days
• Weeks 3-6: Skin symptoms begin improving — reduced scratching, fewer hot spots, less ear discharge
• Weeks 8-12: Full assessment window — if significant improvement has occurred, your vet may recommend a "challenge" phase (reintroducing the original diet) to confirm the food allergy diagnosis

Body Condition Score (BCS) Tracking

Weigh your dog every 2 weeks during the trial. On the 9-point BCS scale:

• BCS 4-5: Ideal — ribs easily felt but not visible, visible waist from above, abdominal tuck present
• BCS 6-7: Overweight — reduce portions by 10%
• BCS 2-3: Underweight — increase portions by 10-15% and consult your vet

Additional Monitoring Markers

• Coat quality: New hair growth, reduced flaking, improved shine by week 6-8
• Stool quality: Formed, brown, easy to pick up — Bristol Stool Scale type 2-3 is ideal
• Energy level: Should remain stable or improve; lethargy warrants a vet check
• Ear condition: Reduced redness, less discharge, decreased head shaking

Frequently Asked Questions About Royal Canin HP

What is the best dog food for dogs with food allergies?

The best food is one that eliminates the offending allergen. For diagnosis, a hydrolyzed protein diet (Royal Canin HP, Hill's z/d, or Purina HA) is the gold standard because the protein fragments are too small to trigger immune responses. For long-term management, either staying on a hydrolyzed diet or transitioning to a single novel protein diet (like Royal Canin Selected Protein or Hill's d/d) based on trial results are both effective approaches. Your vet will guide the choice based on your dog's specific sensitivities.

How much should I feed my dog on Royal Canin HP?

For a typical adult dog at ideal weight with normal activity, feed approximately 1 cup per 15 lb of body weight per day, split into two meals. However, individual needs vary significantly based on metabolism, neuter status, age, and concurrent conditions. Use the feeding table above as a starting point and adjust based on body condition score changes over 2-3 weeks. Your veterinarian should confirm the appropriate portion at your dog's recheck appointment.

Can I feed my dog a homemade or raw diet instead of Royal Canin HP?

A homemade elimination diet is possible but must be formulated by a board-certified veterinary nutritionist to ensure nutritional completeness. The cost is typically 2-4x higher than commercial hydrolyzed diets, and the margin for error is significant — nutritional deficiencies can develop within weeks on an improperly balanced homemade diet. Raw diets are not recommended during elimination trials. The AVMA discourages raw feeding due to documented risks of Salmonella, E. coli, and Listeria contamination, which pose health risks to both pets and their human families. Raw diets also make controlled elimination trials nearly impossible because protein sources cannot be reliably standardized.

What ingredients should I avoid while my dog is on Royal Canin HP?

Avoid all intact protein sources — this includes treats, table scraps, flavored medications, dental chews, flavored toothpaste, bone broth, and pill pockets. Even small exposures can trigger an allergic response and invalidate the elimination trial. Stick exclusively to Royal Canin HP food and vet-approved HP treats for the entire 8-12 week trial period.

How do I switch my dog to Royal Canin HP from their current food?

Follow a 7-10 day graduated transition, starting with 25% HP mixed with 75% old food and increasing the HP proportion every 2 days. The elimination trial clock starts only when your dog is eating 100% HP. If your dog experiences persistent diarrhea during the transition (beyond mild softening), contact your vet — a slower transition or temporary addition of a probiotic may help.

Does my dog need supplements while eating Royal Canin HP?

Royal Canin HP is AAFCO-complete for adult maintenance, so baseline supplementation is not required. However, many veterinarians recommend adding omega-3 fatty acids (20-55 mg EPA+DHA per kg body weight) to support skin barrier repair in dogs with allergy-related dermatitis. Probiotics can also help during the transition period. Always confirm supplement choices with your vet, as some flavored supplements contain intact proteins that can compromise the trial.

How much does Royal Canin HP cost?

As of early 2026, expect to pay $45-60 for a 13.2 lb bag of HP dry food and $55-70 for a case of 12 cans (13.5 oz each). For a 40 lb dog eating approximately 2.75 cups of dry food per day, one bag lasts about 3-4 weeks, putting monthly food cost at roughly $50-80. This is more expensive than standard maintenance diets but comparable to other veterinary therapeutic diets. Some pet insurance policies with wellness riders may partially cover prescription diets.

Can puppies eat Royal Canin HP?

Royal Canin HP is formulated for adult maintenance only — it does not meet AAFCO nutrient profiles for growth. If a puppy requires an elimination diet trial, your veterinarian will select an appropriate alternative or may use a carefully formulated homemade diet under veterinary nutritionist supervision. Never feed HP as the sole diet to a growing puppy without explicit veterinary direction.