Food allergy versus environmental allergy: understanding the differences for your pet’s dermatological health

When dermatological problems arise, such as incessant itching, skin redness or irritation, it is common to think of allergies. Two of the main causes of allergies in pets are food allergies and environmental allergies.

Food allergy: when food becomes a trigger 

Food allergies in pets occur when the immune system overreacts to certain proteins in the food they regularly eat. Symptoms can vary from pet to pet, but include itchy skin, ear infections, vomiting and/or diarrhoea. Meat proteins (chicken or beef), fish or certain cereals are common triggers. 

To diagnose a food allergy, your vet may recommend an avoidance diet, in which potentially allergenic ingredients are excluded from the animal’s diet for a set period (often 8 weeks). If symptoms improve during this period, then return when the pet resumes eating the old diet (challenge diet), this strongly suggests a food allergy. 

Environmental allergy: microscopic particles in our environment 

Environmental allergies are triggered by substances present in the animal’s daily environment, such as pollens, dust mites or moulds. Skin symptoms are like those observed in food allergies, and the respiratory tract can sometimes be affected in cats. The disease is also known as canine atopic dermatitis in dogs. 

The diagnosis of environmental allergies can be more complex than that of food allergies. It is based on clinical signs and the exclusion of other diseases (notably food allergy). Skin tests (intradermal reaction) and/or blood tests (serology) can help identify the specific allergens to which the animal reacts, and above all help choose the allergen extracts to include for desensitisation. 

How do you look after your allergic pet? 

Once your pet’s allergy has been identified, management can vary depending on the type of allergy and the severity of the symptoms.  

• For food allergies, a strict elimination diet is often recommended, with specially formulated foods.  

• For environmental allergies, preventive measures such as regular cleaning of your pet’s environment or the use of products to combat dust mites may be useful. Desensitisation – or immunotherapy – involves regularly administering the substance(s) to which your pet is allergic, to gradually control all or part of the symptoms (skin and/or respiratory) from which it suffers. 

• In the event of damage to the skin barrier, rehydrating and restructuring skin care products are recommended to relieve your pet. 

Conclusion 

While the skin symptoms of food and environmental allergies are similar, their causes and management are different. By working closely with your vet to identify specific triggers and develop a suitable treatment plan, you can help your pet lead a comfortable life.