Chemical Treatments

In general, there are four types of chemicals that are used to exterminate bed bugs.

• Natural pyrethrins: Pyrethrins are made from chrysanthemum flowers, which are grown especially for their insecticidal properties. Pyrethrins are considered to be among the safest insecticides for humans, though they can cause eye, skin and respiratory irritation. Because natural pyrethrins break down fairly quickly, they will put a dent in the bed bug population, but tend not to have the residual effect necessary to kill off an infestation.

• Synthetic pyrethrins: These are chemicals with names like deltamethrin and lambda-cyhalothrin. These have longer residual effectiveness and are generally water-based, so they are less likely to damage furniture or wood than their oil-based natural pyrethrin cousins.
• Inorganic materials, such as diatomaceous earth, silica and boric acid: These will last long, and don’t drive bugs away. They kill by mechanical action – scratching open the bug’s skin so it dehydrates. These materials are good for cracks and crevices, but have to be used in a low-humidity environment. They can leave a whitish film on surfaces.

• Insect growth regulators (IGRs), such as hydroprene: These don’t generally kill the bugs, but instead disrupt their reproductive cycle, so they cannot lay viable eggs.

Some studies have shown that some bed bugs are developing resistance to some of the common synthetic pyrethroid insecticides. States have varying restrictions on the use of chemical treatments, and some of these may not be allowed where you live.