Care for your pet like Vince the Vet

Atopy, also known as atopic dermatitis, is a common skin condition in dogs caused by an allergic reaction to environmental allergens such as pollen, mould, house dust, dust mites and other airborne substances.

It is characterised by persistent or recurrent itching and inflammation of the skin which results in excessive scratching, biting, licking, rubbing or chewing of affected areas (which often include the paws).

This frequently leads to hair loss, the appearance of eruptions / sores and secondary infections with bacteria and / or yeasts.

In many cases the first areas to be affected are the relatively hairless areas of the body where allergens can directly contact the skin, such as the paws, face, ears, armpits, groin and belly.

How is Atopy Diagnosed?

There is no one specific test that confirms atopic dermatitis.

Instead a diagnosis is based on clinical signs (the appearance of the skin), history (itching typically starts between 1 and 3 years of age), and the elimination of other conditions such as flea bite hypersensitivity (still the commonest allergy in dogs) by means of various tests.

The first step involves ruling out parasites and infections with various microbes as a cause.

To do this a vet should carry out a series of basic investigations which include the following:

(a) A close visual inspection of the entire body surface (ideally this should be repeated for all pets in the house).

(b) Examination of:

 • coat brushings

 • acetate (Sellotape) impressions

 • skin debris collected on a wet paper towel 

 • stained smears of skin swabs and discharges under a microscope

 • skin scrapings

 • plucked fur

 • stools

 • culture and sensitivity testing (if indicated)

This helps to identify if dermatitis is the result of:

  • fleas
  • ticks
  • lice
  • mites (including demodex, Sarcoptes, Cheyletiella and Trombicula)
  • bacteria
  • fungi (including ringworm),
  • yeasts
  • internal parasites (such as hookworm) 

Allergy tests are often advised, but these are notoriously unreliable due to the number of false positive and false negative results that occur.

Blood profiles can be useful for ruling out internal disorders which can cause skin signs.

If everything is clear, the only two possibilities that remain is atopy and / or food sensitivities.


Immunosuppressive medication such as steroids, Apoquel, Atopica and Cytopoint for example, should only be prescribed after the tests above have been performed, to avoid these and similar anti-inflammatory drugs being used unnecessarily for parasitic or microbial conditions, which require a very different form of treatment.

PEA is a natural alternative to these drugs which significantly reduces itching in around two thirds of dogs without side-effects.