Atopic dermatitis, otherwise known as allergic skin disease, is a chronic inflammatory dermatological disorder that causes itchiness in dogs. It is a complex disease that is influenced by genetic and environmental factors, involving weaknesses in the skin barrier, allergic sensitisation, microbial infection and inflammation. 

Most dogs with atopic dermatitis will show signs from 6 months to 3 years of age. The commonly affected areas are the paws, face, ears, armpits and belly. Unfortunately, we cannot cure atopic dermatitis. Flare ups are common and lifelong management is often required. 

As the disease has various contributing factors, adopting multiple therapies in our treatment of these itchy dogs is necessary. By doing so, we can keep them comfortable and significantly improve their quality of life. One such therapy is the use of skin supplements, with the aim of restoring the skin barrier. In this post, we’ll explore which supplements are used to help with allergies in dogs and how they work. 

The skin barrier

The skin is the largest organ in a dog’s body and acts as a protective barrier against the environment. The ‘bricks and mortar’ analogy provides a greater understanding of the skin barrier function. The stratum corneum, which is the outermost layer of the skin, is made up of flattened, protein-rich cells called corneocytes – the ‘bricks’ – and these are joined together by intercellular fats – the ‘mortar’. 

Dogs with atopic dermatitis are thought to have a defective skin barrier – even if their skin is visibly normal – due to abnormal corneocyte cells and lipids. This leads to increased water loss and skin dehydration. Furthermore, environmental allergens (such as pollens, for example) are able to penetrate the weak points in the outer layer of the skin and come into contact with immune cells, triggering an inappropriate response that produces itchiness and redness. 

Essential fatty acids

One of the aims of treating atopic dermatitis is to restore and maximise the skin barrier. This can be achieved through the feeding of supplemental essential fatty acids, both the omega-3 and omega-6 kind. These are fatty acids that cannot be produced by the dog’s body and must therefore be given in or addition to the diet. 

Omega-6 fatty acids (such as linoleic acid) have structural importance in contributing towards the ‘mortar’ of the skin barrier. By maintaining hydration of the skin, the skin structure can be restored. In this way, omega-6 fatty acids can help to improve the shine and quality of the dog’s coat. 

Omega-3 fatty acids, such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), prompt increased production of anti-inflammatory compounds. They, therefore, play a role in reducing the inflammation that arises from allergic skin disease. Reducing the clinical signs that occur as a result of itchiness. The recommended dose for combined EPA AND DHA is 60-70mg/kg per day.

How effective are essential fatty acids?

While essential fatty acids can be useful in the management of skin allergies, it is unlikely that they will work alone as the only treatment, especially in the case of acute flare-ups. Patience is required as their use may take at least 8 weeks before results are seen.

They can’t be relied on as a ‘quick fix’ as the fatty acids have to become incorporated into elements of the skin. A study showed that 2 months of omega-3 and omega-6 supplementation resulted in marked improvement of the structure of the stratum corneum in atopic dogs. And, of course, for continued benefits, their use must be sustained. 

Furthermore, essential fatty acid supplementation has medication-sparing properties. Steroids, such as prednisolone, and cyclosporine are immunosuppressive drugs that are often used in the management of atopic dermatitis. It has been found that their dosage can be reduced when omega-3 and omega-6 supplementation is used alongside the medication. 


Vitamin E is a potent antioxidant that protects skin cells from damage. One fairly recent study highlighted that dogs with atopic dermatitis have lower vitamin E concentrations in their blood and that supplementation can reduce clinical signs. Some EFA supplements include vitamin E in their formulation and these may have extra benefits. 

Vitamin A is important for the maintenance of skin tissue integrity and is also involved in regulation of the immune system. 

Some B vitamins, such as vitamin B3 and B5, contribute towards maintenance of the skin barrier function, significantly lowering water loss.


As with most skin diseases, atopic dermatitis can be frustrating to treat. By tackling the problem with multiple therapies, we can try to reduce the level of medication that is needed and improve overall skin health and quality. Supplements are affordable, as well as easy to purchase and administer. While they won’t be able to completely fix the disease, they are a worthwhile adjunct that can have long-term benefits. 

If your dog suffers from skin allergies, your vet will be happy to discuss further the skin supplements that they recommend. 

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