Do Bed Bug Sprays Work? What Store Products Miss

Store-bought bed bug sprays kill the bugs they soak and little else. UC IPM does not generally recommend over-the-counter products, and it reports that some bed bug populations now resist pyrethroids. Foggers are worse: the mist misses the cracks where bed bugs hide and pushes survivors deeper into walls. Professional treatment adds products with different modes of action, a fungal biopesticide, dusts placed where they stay dry, and follow-up visits timed to egg hatch.

Do store-bought bed bug sprays work?

They work on the bugs you hit while the spray is wet, and not much after that. UC IPM says over-the-counter products with bed bug claims "aren't generally recommended" because their performance under field conditions isn't known. The University of Kentucky adds that most sprays made for householders have limited effect once they dry.

A spray reaches only what you can see. Bed bugs rest in mattress seams, bed frames, baseboard cracks, nightstands and the clutter under the bed. UC IPM says the eggs hatch in about 10 to 15 days at room temperature. Each round kills a few adults, leaves the eggs, and selects for the bugs that tolerate the product.

Why don't pyrethroid sprays kill bed bugs anymore?

Because the bugs have adapted. UC IPM reports that some bed bug populations have developed resistance to pyrethroids and that insecticide resistance among bed bugs "is increasingly common." Ohio State University Extension says pyrethroids were once among the best defenses, until overuse and misuse produced highly resistant strains.

In a Penn State and North Carolina State study, three resistant field strains showed only 16 to 40 percent mortality 14 days after deltamethrin exposure. Two of those strains survived as well as bugs exposed to plain water. More spray only leaves the survivors to breed.

Why do bug bombs make a bed bug problem worse?

Because the fog never reaches the harborage, and the ingredients repel the bugs it does reach. The University of Kentucky's fogger fact sheet explains that very little insecticide penetrates the cracks, voids and secluded spots where bed bugs spend their time. The ingredients also "tend to be repellent, causing insects to scatter and move deeper into walls, crevices, and other hard-to-reach areas." Ohio State adds that foggers generally do not kill bed bugs even on direct contact.

In an apartment, "deeper into walls" can mean the unit next door, since bed bugs travel between rooms and floors through cracks in walls, floors and ceilings. That is how one fogged unit spreads the problem, as our post on bed bug treatment in Los Angeles apartments describes. Foggers also settle residue on counters and bedding, and they have caused house fires when pilot lights were left burning. UC IPM calls them ineffective and potentially harmful to residents.

Do desiccant dusts like diatomaceous earth kill bed bugs?

Silica gel does when it is applied correctly. Diatomaceous earth rarely helps. UC IPM says dusts cling to the insect's cuticle and can provide long-term control as part of an integrated program. They belong where they stay dry, such as under baseboards or in wall voids.

The University of Kentucky is blunter: diatomaceous earth is messy to apply and "will seldom help much," while silica gel "can be very effective, though, if applied correctly." Correct means tiny, barely visible amounts brushed into seams, folds and crevices, with eye protection and gloves.

What do professional bed bug products add that store sprays don't?

Different modes of action, products placed where the bugs travel, and a biopesticide with no known resistance. UC IPM says the most effective bed bug pesticides are limited to commercial applicators and that confirmed infestations belong with trained professionals. Liquids go on cracks, crevices, bed frames and baseboards, and not generally on mattresses or bedding.

Mixed chemistry. UC IPM lists pyrethroid and neonicotinoid mixtures and the pyrrole chlorfenapyr, which may take many days to kill. Ohio State notes that pyrethroids are now generally applied with synergistic insecticides rather than alone. UC IPM cautions that some studies suggest pyrethroid mixtures still drive resistance.
A fungal biopesticide. Beauveria bassiana is a natural fungus that causes disease in insects. In the Penn State study, bugs that crossed a treated barrier picked up spores and spread them through the harborage. It killed 95.5 to 99 percent of all four strains within 14 days, with no known resistance or cross-resistance. PesPro's bed bug treatment combines chemical and fungal treatments.
An insect growth regulator. UC IPM lists hydroprene among the newer product types and notes it may take many days to kill.

Why does bed bug treatment need follow-up visits, and are they included in the quote?

Because eggs keep hatching after the first visit, and one treatment is rarely enough. The University of Kentucky says follow-ups are usually needed, and Ohio State says infestations often require more than one treatment. UC IPM advises inspecting after treatments to be sure the bugs are gone. The follow-up is where the technician finds and treats the hatch.

At PesPro the inspection comes first, because severity sets the scope. The written quote that follows is free and covers the initial treatment and follow-up visits as one plan. Follow-ups are paid and written into that plan, not given away. The 30-day guarantee is separate: if bed bugs reappear within 30 days, we return for a third visit at no extra cost.

How should you prepare so the treatment actually works?

Launder, clear the clutter, and do not spray anything before the technician arrives. The University of Kentucky says bedding and garments often need laundering at 120°F minimum, since they cannot be treated with insecticides. A clothes dryer on medium-to-high heat for 10 to 20 minutes also kills all life stages.

Clutter under and around the bed often has to go, because it blocks the treatment and hides bugs. Nightstands and dressers may need to be emptied and examined. Encase the mattress and box spring so any bugs sealed inside eventually die. Our bed bug prep checklist walks through every step.

If you have live bugs tonight, same-day service is available for an extra fee and depends on the day's route. Request a free written quote or call (323) 472-5329. Our bilingual technicians cover every city on our service area list.

Frequently asked questions

Should I spray the room before the technician comes?

No. Foggers repel bed bugs and push them deeper into walls and furniture, and store sprays only kill the bugs they wet. The technician then finds fewer bugs and treats fewer harborages. Strip the bed, launder on high heat, and leave the bugs where they are until the inspection.

Are "natural" bed bug sprays a safer bet?

Not usually. Ohio State University Extension notes that natural or "green" products are exempt from EPA registration and are not required to demonstrate efficacy. It calls many manufacturer claims unsubstantiated. A product that kills the bugs you soak still misses the eggs and the harborage. Treat efficacy claims as marketing until an extension source confirms them.

How many visits does professional bed bug treatment take?

Plan for an initial treatment and at least one follow-up, because eggs keep hatching for about two weeks after the first visit. The count depends on severity and preparation, which is why PesPro quotes after the inspection. Follow-ups are part of the quoted plan. The 30-day guarantee adds a third visit at no extra cost if bed bugs reappear.

How do I check that a bed bug company is licensed in California?

Look up the company through the Structural Pest Control Board's license page, which sends you to the Department of Consumer Affairs license search. You can search by business name or license number, and the "Board and Bureaus" field narrows results to this board's licensees. PesPro holds California Structural Pest Control Board License #PR-6378. Do not hire anyone who cannot give you a number to check.