The Allergy Threshold


The term allergy threshold is often mentioned when talking about allergies in both humans and animals, but what does it actually mean?

One analogy that’s been used to help explain it is the humble bucket. When there is too much water in the bucket, it spills over and that makes a mess. Nobody is worried when the bucket is half full because it doesn’t cause anyone a problem. Likewise, when your allergy burden gets too high, you tip over the allergy threshold and then see the signs associated with allergy for example itching, scratching or sneezing.

We used to think one allergen, be that a pollen or dust mites for example, was responsible for ‘filling the bucket’. More recently, it has become apparent it is far more likely several different allergens, whether they are in our food or from the environment, each contribute to getting you closer to that threshold or point of overflow. For this reason, it’s really important to try and control multiple aspects of allergic diseases. The less that goes into the bucket day to day, the more leeway you have if you suddenly get a downpour!

It is suggested that 10-15% of dogs in the UK are affected by allergic disease, and it is being recognised with increasing frequency in cats.


The allergy Threshold - environmental allergens

In this dog, only environmental allergens are present and these are above the allergic threshold so clinical signs are seen. If completely controlled the clinical signs should resolve. The same would apply if food allergens were present in isolation and above the threshold.

The Allergy threshold - food allergies

The combined allergic stimulation from the environmental and food is below the threshold so no clinical signs are seen. In this case, if any intermittent compounding factors such as ectoparasites or seasonal pollens were added, the allergenic stimulation could easily then go above the threshold and cause clinical signs.

The allergy threshold - multiple allergies above the threshold

The combined allergenic stimulation is above the threshold so clinical signs are seen. Clinical signs could be managed by either controlling dietary or environmental allergens but by only considering one aspect the pet is left close to the threshold and therefore vulnerable to compounding factors.

The allergy threshold - allergenic stimulation with clinical signs

The allergenic stimulation is above the threshold so clinical signs are seen. It is not only in combination that this will occur as both environmental and food allergens individually are above the threshold. Even if one component is completely controlled there may not be a reduction in clinical signs. Both must be identified and controlled for resolution.

By identifying exactly what allergens are contributing to your pet’s symptoms enables a more personalised approach to management and treatment, helping to ensure ‘the bucket’ doesn’t spill!

Speak to your vet for further advice about whether allergy testing is right for your pet.


Share this Article