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What Kills Bed Bugs? Understanding Insecticides

Bed bugs have been a scourge on humanity for, quite literally, as long as humanity has existed. We’ve naturally been trying to kill them for just as long, and traditional methods include such questionable remedies as black pepper, wild mint, and cannabis (which if nothing else takes some of the stress out of an infestation).

Thankfully, our ability to counteract these blood-sucking parasites has advanced somewhat— though so too has the frequency of bed bug infestations, which has been on the rise since the 1980s. More modern methods of killing bed bugs include a variety of specialized chemicals, fumigation, and mechanical techniques.

Unfortunately, like the heavy sleepers they prey on, bed bugs are cozy right where they are — once they’ve settled somewhere, it’s incredibly difficult to make them get up and go. Serious infestations must be treated with a combination of different chemicals, cleaning techniques, and a hefty dose of time and patience; however, this can all be done DIY.


Despite the fact that bed bugs have increased their resistance to pesticides (alongside their increase in numbers), chemical treatments are still an important part of any eradication strategy. Which chemicals, and how important a part they’ll play, depends on the infestation itself. Bed bug populations in different states have developed resistances to different products, and even the method of application (liquids, aerosol sprays, powders, etc.) can make a difference in the treatment’s efficacy.

The EPA has registered over 300 pesticide products for use against bed bugs, many of which are designed to be applied directly by consumers in their own homes. In this article, we’ll review some of the most common and effective ones you can use yourself.

Chemical Classes

There are seven distinct classes of chemical pesticides used for bed bug control. Each of these classes kills via a different “mode of action,” meaning that resistance to one method is no guarantee of resistance to another. Using a combination of different chemicals, then, increases the chance of finding one that works well on a particular infestation of bed bugs.

Here’s a quick run down of each class of chemical, as well as their distinct modes of action:

Pyrethrins and Pyrethroids

The most common chemicals used for indoor pest control — bed bugs included — are pyrethrins and pyrethroids, which are similar but distinct compounds (the difference is that pyrethrins are derived from real chrysanthemum flowers, while pyrethroids are mere synthetic imitators). Both classes of chemical kill bed bugs by messing with their nerve function and causing paralysis — a tough but fair death sentence for any parasite.

Unfortunately, resistance to pyrethrins and pyrethroids is not uncommon among certain bed bug populations, so the application of these chemicals may not be wholly effective. Combining multiple products can increase their potential for success, but for tough populations, it may be necessary to switch to a different class of pesticide entirely.


Desiccants are drying agents; they dehydrate insects to kill them. They work on bed bugs by attaching to their waxy exoskeletons and absorbing the juicy fats and vital moisture within. A chief advantage of desiccants over other pesticides is that this process is mechanical in nature, not chemical — which means it’s impossible for bugs to develop resistance. It also means the substance is generally safe for use around humans and pets, who keep their skeletons on the inside, thank you very much.

Desiccants commonly used to treat bed bugs include Cimexa Dust (silicon dioxide; our favorite), Diatomaceous Earth, and sometimes Borax (a salt of boric acid). These substances come in the form of fine powders that can be sprinkled around cracks, crevices, and furniture. While effective at killing bed bugs, desiccants like these can take days or weeks to do so, which may leave the insects enough time to reproduce. As with most of these methods, desiccants will be most effective when used alongside other chemicals and treatments.

Cold Pressed Neem Oil

Sourced from the seeds of tropical Neem trees in Southeast Asia and Africa, cold-pressed neem oil is classified as a biochemical pesticide (meaning biologically derived, as opposed to chemically synthesized). The oil, which is applied as a spray, is both an insecticide and an insect repellent — so bed bugs will actively avoid it, rather than letting it kill them. On the other hand, this same property can be useful in keeping the bugs (and their famous bites) away from you while you sleep. It’s important to note also that neem oil loses its potency after about a week, well before it could fully eradicate an infestation. Once more, it’s merely one part of a balanced, multi-pronged treatment strategy.

In addition to repelling insects, neem oil’s inherent medicinal properties make it a useful ingredient in hygiene products like shampoos and soaps.


Pyrroles (like the pesticide Chlorfenapyr) do not kill bed bugs on their own; rather, they’re considered a “pro-insecticide” that becomes deadly only after entering their hosts. Once inside an insect, pyrroles are metabolized in the body and become a new, more lethal chemical. This new compound works by disrupting the production of adenosine triphosphate (ATP), a molecule required by all forms of life to transfer energy between cells. Without ATP, bed bugs literally lose the power to live.


Neonicotinoids are the most widely-used class of insecticide in the world. Composed of synthetic forms of nicotine (which apparently is no better for bugs than it is for us humans), neonicotinoids wreak havoc on an insect’s nervous system. Specifically, these chemicals cause a bed bug’s nerves to fire repeatedly until they fail — permanently. As with pyrethrins and pyrethroids, the end result of neonicotinoid exposure is paralysis and death. However, as the mode of action between these chemical classes is distinct, bed bugs who are resistant to one may still be vulnerable to another.

Insect Growth Regulators

An insect growth regulator (IGR) is a special type of chemical that mimics growth hormones in order to stunt or alter an insect’s development. By throwing each insect’s life cycle out of whack (bed bugs go through six stages on their way to adulthood, each more upsetting than the last), the population as a whole becomes unable to properly sustain itself through reproduction.

Whereas other insecticides are used to kill individual bed bugs, IGRs are used to gradually extinguish the population as a whole. They’re useful as a method of control in the long term and are usually used alongside chemical treatments that kill bed bugs on contact. And because IGRs target insect hormones specifically, many are non-toxic and safe to use around children and pets. This can be a useful strategy for very large infestations; however, research shows IGRs may be more effective against fleas and ticks than bed bugs.

Mechanical Methods

As useful as chemical solutions are in dealing with a bed bug infestation, they must be used in conjunction with more manual treatments in order to be effective. The following methods are useful both to help control an existing infestation as well as to proactively prevent bed bugs from spreading in the first place:


Bed bugs are drawn to the warmth of a human body, but that’s about as hot as they like it. An hour’s exposure to temperatures of 113 °F will destroy all bed bugs at any stage of life — eggs included — and anything hotter than 180 °F will kill them immediately. Conveniently, putting clothing and bedding in a high-temperature dryer for about half an hour should do the same trick.

For this reason, and others, regularly washing your clothes and linens is advised. To be extra thorough, you can even do this with small items like shoes and stuffed animals.

For items that can’t go in the dryer — like furniture or mattresses — a thorough steam cleaning will work just as well. For severe infestations, specialized heating units exist that can raise the temperature of entire rooms for hours with the aim of sweating out all the bed bugs hiding within. This solution, while effective, is expensive and prone to causing fires.


Bed bugs dislike the cold almost as much as they hate the heat, which is to say: four days below 0 °F kills them just as dead, and colder temperatures will kill them even quicker. Though it’s not practical to eradicate a full infestation this way, you can easily remove bed bugs from specific items — books, clothes, jewelry, toys — by putting them in a plastic bag in your freezer. Be sure to use a thermometer to verify that the minimum appropriate temperature is met.


Bed bugs can spread anywhere, from the filthiest hovel to the swankiest hotel. That said, less clutter means fewer places for bed bugs to hide, and greater odds of spotting them before they become a problem. For this reason, and others, regularly vacuuming your bedroom and decluttering your house is recommended. If you know you have bed bugs, you should scrub down the area around your bed before vacuuming to pick up as many eggs and insects as possible; just remember to throw out your vacuum cleaner bag after you do so nothing left alive can escape.

To really go the distance, consider purchasing a zippered encasement to cover your mattress and box springs. These covers are designed to keep bed bugs either in (if you’ve got them already) or out (if you want to keep it that way). If you can sleep easy knowing there are bed bugs trapped beneath you, be prepared to do so for a while: the creatures can survive for up to a full year without feasting. Only then should you feel comfortable removing the cover.


Chemical pesticides and mechanical methods like heat are straightforward ways to control bed bug populations, but sometimes a heavier hand is needed to fully eradicate an infestation. In these situations, fumigation — filling the entire affected area with poisonous gas — is effective if drastic solution. Because it’s such an invasive process, fumigation should be used as a last resort and should be conducted only by professional fumigators.

(Note that there are consumer fumigation products, such as “total release foggers,” that can apply pesticide in the form of a gas. While potentially helpful, these products are not effective as the sole method for bed bug eradication — unlike professional fumigation.)

How Fumigation Works

Professional fumigation is an intensive (and likely expensive) process that requires significant preparation. The area to be fumigated must be cleared of all consumables (like foodstuff) and completely sealed while the fumigants (gases) do their work. These fumigants are harmful to humans, pets, and plants as well as bed bugs, so the room is off-limits while they’re present.

If the infestation is severe enough, the entire property may have to be tented up and fumigated at once. This is an even harsher process because, in addition to removing all food, plants, and linens, you’ll have to find somewhere else to stay for a few days (the exact duration of this process will depend, but can take as long as a week).

Once the fumigation is finished, the gases must be fully ventilated before the area is safe to enter. At that point, you can begin the job of sweeping up hundreds of dead bed bugs — which, since they put you through all this, may prove to be a more cathartic chore than most.

What’s the Best Method to Kill Bed Bugs?

We recommend our readers to use a combination of Cimexa Dust and steam cleaning around the mattress to eradicate bed bugs and use pyrethrins/pyrethroids around baseboards, among a few other tips and tricks. Follow our full 6 steps on getting rid of bed bugs for the complete strategy.

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Written by Wesley Wheeler

Wesley has over 10 years of residential and commercial pest control experience dealing with every kind of pest. He ran his own pest control company for 6 years and now shares his knowledge online.

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