During each of the four stages of the flea life cycle, fleas are resistant to different chemicals. For best results at killing fleas in all stages, use products that contain an insecticide as well as an insect growth regulator.
Eggs are laid on your pet, in the hair coat, and then fall off in your house when your pet comes inside. Flea eggs are resistant to most insecticides, but can be controlled with growth inhibitors. In the home, another effective way to eliminate flea eggs is with intensive cleaning and vacuuming. See our page on home flea control for more information.
Flea larva develop inside your home and feed on flea excrement that fall out of your pet’s hair. Larva can be controlled with insecticides, borates and growth inhibitors.
Adult fleas usually emerge from the pupae when a host pet is around. They are very mobile, but can only survive a few days without a host, or if they are dislodged from their host.
As you can see, fleas at different stages of their life cycle are resistant to certain flea control methods. For this reason, it’s important to attack all stages of the flea life cycle with different methods and products.
In case you’re still not getting it, check out this in depth video on the flea life cycle, as well as flea behavior.