By Chris Williams on July 3, 2017.

I read on your website that you use a growth regulator for flea control. What is that all about? I don’t want them to grow, I want them gone! Bring on the pesticide! L. W., Beverly, MA

We hear you. An insect growth regulator (IGR) is not an insecticide in the traditional sense but is usually used as part of an insecticide treatment. The addition of an IGR goes above and beyond regular flea control measures, giving you an extra measure of confidence that the fleas will be gone. In fact, when you (or your veterinarian) treat your pet for fleas, chances are you are using a product containing an insect growth regulator.

An insect growth regulator is an innovative chemical that blocks the normal development of an insect by interfering with its hormones. An IGR can prevent flea larvae from molting and growing, or can prevent emergence from the pupal case (so they never become biting fleas), or prevents reproduction by blocking egg hatch or producing sterile adults.


The down side to an IGR is that it doesn’t kill insects outright but kills them in the long-term by preventing the next generation. This concept is harder to accept when we are talking about fleas that are biting now, which is why we combine an IGR with our regular insecticide treatment of flea areas in your home. We know you and your pets want immediate relief from fleas.

In some cases, we do use an IGR by itself, but only as a preventative measure when fleas are not already a problem (see IGRs Used Early Stop Flea Development for Good). The dual approach of using an IGR along with an insecticide is always better than using an insecticide alone. The killing effect of the insecticide used lasts for a long time, but the effects of the IGR last even longer and will continue to affect fleas that were missed during treatment and those that have hatched from eggs after the treatment. Since IGRs only affect insects, they are considered safe for use around people and pets.


Flea season is getting cranked up here in the Northeast and flea problems will only increase between now and the first hard frost (see Fleas Can Reinfest Your Home From Outside). Call Colonial at the first sign of a flea problem. And remember that our treatment of your home is only one aspect of a flea control program. Your pet must be treated for fleas as well. Our technician can walk you through the whole process and can explain what to expect with our IGR dual program.

For more on what we do to control fleas in your home, see Flea Elimination in our Services section of the website and give Colonial a call today!

Photo Credit : Rayaah

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