Food allergies are a less common but significant health concern for cats, often presenting with noticeable symptoms affecting both their skin and digestive systems. While rare, they are the third most frequent type of allergy in felines, following flea allergies and environmental triggers like pollen and dust. Identifying and managing a cat’s food allergy is a crucial step in ensuring their well-being, and it’s a process best undertaken in close collaboration with your veterinarian.
Food allergies in cats are characterized by an overreaction of the immune system to specific food components previously encountered. This triggers the production of antibodies, leading to inflammation and a range of symptoms. The most common culprits are proteins found in beef, chicken, and fish, although any food ingredient can potentially cause a reaction. Diagnosing a food allergy necessitates a strict eight to 12-week hypoallergenic food trial, during which no other treats or flavored medications are permitted. Long-term management typically involves lifelong dietary adjustments to avoid trigger ingredients, with potential need for symptomatic treatments to manage flare-ups.
Key Takeaways
- Food allergies in cats, though rare, can manifest as persistent itching, skin lesions, and sometimes gastrointestinal issues such as vomiting or diarrhea.
- Proteins like beef, chicken, and fish are the most frequent allergens, but cats can react to a wide array of ingredients.
- Diagnosis relies on a rigorous 8- to 12-week hypoallergenic food trial, excluding all other food sources.
- Ongoing management requires permanent dietary changes to avoid trigger ingredients, and supportive care may be needed for temporary symptom control.
What Are Food Allergies in Cats?
A food allergy in cats occurs when their immune system mistakenly identifies a food substance as a threat and mounts an inflammatory response. The immune system generates antibodies against a protein that should normally be harmless. This inflammatory reaction can lead to symptoms such as intense itching, the development of sores, and gastrointestinal distress.
For a cat to develop an allergy to a specific food ingredient, they must have consumed that ingredient in the past. Food allergies are not very common in cats; it is estimated that only about 1% of all cats are affected, though they account for up to 15% of itchy cats. Among cats exhibiting both itching and gastrointestinal symptoms, the prevalence of food allergies can rise to as high as 42%. While most cats develop food allergies after they are over one year old, cats of any age or gender can be susceptible. Some research suggests that Siamese cats and mixed breeds may have a higher predisposition to food allergies.
Cat Food Allergy Symptoms
The hallmark symptom of a food allergy in cats is persistent itching that isn’t seasonal. This itchiness can affect any part of the body, but it most frequently targets the head and neck.
Other common symptoms include:
- Excessive licking
- Frequent scratching
- Biting at the skin
Skin lesions are also common and can appear as:
- Small crusts (miliary dermatitis)
- Reddened skin
- Self-inflicted wounds from scratching, biting, or licking
- Ulcers
- Raised, circular nodules (plaques)
Gastrointestinal symptoms, such as diarrhea and vomiting, are less common but can occur.
What Causes Food Allergies in Cats?
A cat can develop a food allergy at any age, even if they have been eating the same food for an extended period without any issues. The underlying cause is typically an abnormal immune response to proteins present in the cat’s diet. While certain foods are more commonly implicated, any food ingredient can potentially trigger an allergic reaction.
The food sources most frequently associated with food allergies in cats include:
- Beef
- Fish
- Chicken
Less common triggers can include:
- Dairy products
- Lamb
- Eggs
- Barley
- Rabbit
How Veterinarians Diagnose Food Allergies in Cats
Veterinarians typically diagnose food allergies in cats through a meticulous food elimination trial. This process involves two key phases:
- Hypoallergenic Diet: The cat is fed a strictly hypoallergenic diet for a period of eight to 12 weeks.
- Reintroduction: If the cat’s symptoms significantly improve during the trial, their original diet is then reintroduced. A recurrence of symptoms confirms the diagnosis of a food allergy.
Two primary types of diets are used for this trial:
- Novel Protein Diet: This diet is formulated with a protein source the cat has never consumed before, such as duck, venison, or alligator.
- Hydrolyzed Protein Diet: In these diets, proteins are broken down into smaller molecules that are less likely to be recognized by the immune system as allergens.
It is important to note that current blood, hair, or saliva tests marketed for diagnosing food allergies in cats have not been proven accurate in clinical studies.
To ensure the success of a hypoallergenic diet trial:
- Provide a complete diet history: Share all of your cat’s past and current food intake with your veterinarian to aid in selecting the most appropriate diet for the trial.
- Strict adherence: Do not feed your cat any other food, treats, or flavored medications. Even small deviations can trigger an allergic response and compromise the trial’s results.
- Patience is key: Some cats may not respond to the first hypoallergenic diet but may improve on another. The process requires time and persistence.
Treatment of Food Allergies in Cats
The cornerstone of treating a food allergy in cats is to maintain a diet free from the specific ingredients that trigger their allergic reactions, as identified through a successful hypoallergenic diet trial. Veterinary therapeutic diets are often recommended because they have stringent quality control measures to prevent cross-contamination with other proteins.
In some cases, a veterinarian might suggest an over-the-counter diet from a reputable brand that features a single-source protein. However, these foods can sometimes contain contaminants from other proteins processed on shared equipment, which may still provoke a reaction in sensitive cats.
During the initial stages of a hypoallergenic diet trial, cats often experience significant itching. Symptomatic treatments may be necessary to provide relief while the old food is cleared from their system and the new diet takes effect, a process that can take eight to 12 weeks. Low-dose corticosteroids, such as prednisolone, are frequently used for this purpose. Additionally, any secondary bacterial or yeast infections that develop due to skin damage must be treated with appropriate antibiotics and antifungals.
Food Allergies in Cats FAQs
What is the most common food allergy in cats?
The most common food allergens in cats are animal proteins, with chicken, fish, and beef being the top three culprits. Dairy products are also a frequent cause of allergies.
Can cats be allergic to chicken?
Yes, chicken is one of the most common food allergens in cats. Chicken allergies typically manifest as itchy skin and related issues, but can also lead to gastrointestinal upset.
How do you figure out what your cat is allergic to?
Determining a cat’s specific food allergies is best done through a hypoallergenic elimination diet trial conducted under veterinary guidance. Feeding a veterinary diet with a novel or hydrolyzed protein for at least eight to 12 weeks can help pinpoint trigger foods.
Can a cat allergy cause diarrhea?
Yes, food allergies in cats can cause diarrhea. While skin issues are more prevalent, studies indicate that approximately 18% of cats with food allergies experience digestive symptoms, including diarrhea and vomiting.
References
Bryan, Jacqueline & Frank, Linda A. (2010). Food Allergy in the Cat: A Diagnosis by Elimination. Journal of Feline Medicine and Surgery.
Jackson, Hilary A. (2023). Food allergy in dogs and cats; current perspectives on etiology, diagnosis, and management. Journal of the American Veterinary Medical Association.
