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Do Flea Bombs Work?
Flea bombs kill the adult fleas they reach, but most of a flea problem isn’t adult fleas. Around 95% of fleas in a home are eggs, larvae and cocoons hidden deep in carpets, furniture and floor gaps, and the fog doesn’t reach them. Used on its own, a flea bomb rarely clears an infestation: fleas usually come back within a couple of weeks.
This guide explains why, how to use a flea bomb safely if you still want to, and what works better.
- Why flea bombs don’t kill all the fleas
- Do flea bombs kill flea eggs?
- How to use a flea bomb
- How long before you can go back in
- Are flea bombs safe?
- What works better than a flea bomb
What is a flea bomb?
A flea bomb, also called a flea fogger or total release fogger, is a can of insecticide that empties itself in one go. You set it off in the middle of a room and leave. The insecticide fills the air as a fine mist or smoke, then settles on the floor and on every surface it lands on.
Types of flea bomb in the UK
- Aerosol foggers – a pressurised can that sprays a mist once you press the tab down.
- Smoke bombs – a small canister you light, which gives off insecticidal smoke. These can set off smoke alarms.
Most contain an insecticide that kills adult fleas, and some add an insect growth regulator (IGR), which stops eggs and larvae developing into adults. Check the label: a flea bomb with an IGR does more than one without.
Why are flea bombs not killing the fleas?
A flea bomb only kills what the mist touches. It settles on open floors and the tops of furniture, but flea larvae live at the base of carpet fibres, under sofas and beds, and in the gaps along skirting boards. Flea cocoons are worse still: insecticides don’t affect them, and the young fleas inside can wait for months before they hatch. That’s why new fleas usually appear 10–14 days after a treatment.
| Flea stage | Where it lives | Does a flea bomb kill it? |
|---|---|---|
| Adult fleas | On pets, and jumping on open floors and bedding | Yes, if the mist reaches them. Fleas on pets aren’t affected, as pets are out of the house. |
| Eggs | Fall off pets into carpets, sofas and pet beds | Only with an IGR, and only on exposed surfaces |
| Larvae | Deep in carpet fibres, under furniture, in floor gaps | Rarely – the mist doesn’t get down that far |
| Cocoons | Same places as larvae, stuck to carpet fibres and dust | No – insecticides don’t affect them |
The result: the adult fleas die, the bites stop for a week or two, and then the next batch hatches.
Do flea bombs kill flea eggs?
Only some do, and only the eggs the mist reaches. A flea bomb with an IGR can stop eggs and larvae on open surfaces from developing, but eggs that have dropped deep into carpets and cracks are out of reach. Plain insecticide bombs don’t affect eggs at all. See what flea eggs look like and where to find them.
How do flea bombs work?
Once you set it off, the can releases all its insecticide into the room. The mist hangs in the air for a few hours, then settles on surfaces and kills adult fleas on contact. Because it falls from above, it treats what’s exposed (open floor, bedding left out, tops of cushions) and misses anything underneath or inside.
How to use flea bombs?
If you decide to use a flea bomb, the label is the rule: how many rooms one can covers, how long to stay out and when you can hoover. These are the general steps.
Prepare the space
- Treat your pets for fleas first – ask your vet which product to use.
- Hoover all floors and furniture, then empty the hoover outside.
- Put food, plates, cutlery, toys and pet bowls away, and cover fish tanks.
- Open cupboards, drawers and internal doors so the mist can get in. Keep windows and outside doors shut.
- Turn off pilot lights, gas fires and electrical appliances – aerosol foggers are flammable.
- If you’re using a smoke bomb, cover or switch off smoke alarms as the label says.
Activate the flea bomb
Use one can per room unless the label says otherwise. Stand it on a chair or a sheet of newspaper in the middle of the room, set it off and leave straight away. Everyone – people and pets – has to stay out for the time on the label.
Come home
Open the windows and leave the rooms to air before anyone goes back in. Wipe surfaces where you prepare food, and wash bedding and pet beds that were left out. Remember to switch smoke alarms back on.
Monitor flea activity
Expect to see some new fleas over the next few weeks as cocoons hatch. Keep hoovering, keep your pets’ flea treatment up to date, and use a targeted flea spray on the spots the bomb can’t reach. If fleas are still there after four weeks, the infestation needs a stronger treatment.
How long after a flea bomb can you go back in?
It depends on the product, so always go by the label – for most flea bombs it’s a few hours. When you go back in, open the windows and let the rooms air well before children or pets come home.
Are flea bombs safe?
Flea bombs are safe enough when you follow the label, but they fill your whole home with insecticide, so most of the risk comes from going back in too early, using too many cans or using them near a flame.
Are flea bombs safe for children and babies?
Keep children and babies out of the house for the full time on the label and until the rooms have aired. Wash anything they may touch or put in their mouth – toys, bedding, high chair trays – before they use it again. If you have a baby at home, a targeted spray used only where fleas are is a better choice than a fogger.
Are flea bombs safe for cats and dogs?
Take all pets out of the house, including fish tanks (cover and switch off the pump) and caged pets. Some flea products contain permethrin, which is safe for dogs but poisonous to cats, so check the ingredients before using any flea product in a home with a cat. Wash pet beds and bowls before your pets come back, and if you’re unsure which product to use, contact your vet.
Fleas came back after a flea bomb?
Our technicians spray the carpets, floors and furniture a flea bomb can’t reach, with a return visit to catch fleas hatching from cocoons.
Professional flea treatment covers your whole home in one visit.
What works better than a flea bomb?
Fleas need to be treated at every stage at once – on your pet and in your home:
- Treat every pet. Use a vet-recommended flea treatment on every cat and dog in the house, or new fleas will keep arriving.
- Use a targeted spray. A household flea spray with an IGR can go under furniture, along skirting boards and into the places fleas actually live.
- Hoover daily. The vibration makes cocoons hatch, so the new fleas meet the insecticide sooner.
- Wash bedding hot. Pet beds, throws and bedding go on the hottest wash the fabric allows.
Our guide on how to get rid of fleas in the house covers each step. If fleas keep coming back, our flea treatment uses a residual spray that keeps working for weeks, with a return visit after two weeks and a 3-month guarantee.
Our goal is to provide valuable information regarding fleas and possible health risks associated with them. But we as a commercial service provider cannot give you any medical advice.
