Cat scratching her head.


Ctenocephalides canis (common dog flea) is by far the most common external parasite seen on dogs and cats. As most pet owners will attest to, these pests are the number one health problem facing these pets.

However, aside from causing relentless chewing and scratching, fleas are also disease carriers, and can threaten the pet owner’s health as well. For these reasons, the development of a good control program to combat these irritating pests is a must.

It is important to understand that fleas spend the vast majority of their time off of the pet, reproducing and maturing in the pet’s environment. As a result, environmental control measures are essential for successful flea control.

The flea life cycle includes four major stages: egg, larva, pupa, and adult stages. Both the egg and pupa stages are very resistant to insecticides, which can make complete flea control difficult.

During summer months, the entire flea cycle (egg to adult) might be completed in 16 to 21 days. Heat and humidity tend to shorten this cycle period. In addition, fleas are most prolific during hot humid weather. A complete approach to flea control should always involve three steps:

  1. Treating the home
  2. Treating the yard
  3. Treating the pet

Because fleas, on average, will only spend about 10 percent of their time on dogs and cats, treating the surrounding environment is probably more important than treating the actual pet.