flea allergyWe have created previous articles on parasite and in particular Flea issues causing dog allergies before on this site. We have provided all of the technical  reaction information but this article is more about how to avoid and why.

I know many people at dog parks who think that fleas only breed in summer and that their dogs are safe without flea pesticides for the rest of the year.  This is mostly a way of saving money and is based on ignorance of the flea.   Fleas like many insects might be more active or obvious in summer, but unlike snakes and reptiles, fleas breed all year round and your dog can get terrible allergy reactions unless you guard against them all year round.

Just like children who are not vaccinated going to schools can cause children who have had vaccinations to still catch a virus, so can dogs not given flea medication, infect dogs that have had protection.

You might ask how this is possible and what the value of flea protection via chemicals is and its pretty simple.  Your dog can pick up fleas from the grasses they live in, or by getting up close with other dogs.  Fleas get most of their sustenance from the blood of animals (just like ticks)

some quick tips on fleas

  • 4 life-cycle stages :  egg, larva, pupa, &  imago (adult).
  • Adult fleas must feed on blood before they can reproduce.
  • Flea populations typically are: 50% eggs, 35% larvae, 10% pupae, and 5% adults.

Note even dogs kept inside all of the time can get fleas from association with cats that go outside or fleas that come in under doors.

Note fleas can cause pain, drain a dogs energy, tax its immune system, cause secondary infection and hot spots on the skin that cause a large bleeding rash.


While the chemicals used for flea treatment are often applied to the back of the neck or in tablet form once per month, not all dogs can handle these chemicals, and some dogs need more chemical than provided in the dose.

The biggest issue for dogs is that the chemicals dont always kill all of the flea life cycle stages.

Advantage pack I have says kills flea adults, and flea larvae.  It does not mention if it kills flea eggs.

The sentinel pack I have is supposed to kill most dog worms, including heart worm it says it “prevents and controls fleas long term”.  HOWEVER on the back of the pack it says “DOES NOT KILL ADULT FLEAS”.

It seems that because of patents or prices that not all dog mediation against fleas kills every one of the flea stages. This means that the stage that can live on the dog will do so and might cause skin allergies on them.

Always check how effective and against what Flea stage your dog flea medication is useful for.