Does Listerine Kill Roaches?

Since they’re so common, it’s vital that people know how to kill roaches, including the ones they’re living with.

Some people get an active ingredient in Listerine, such as chlorhexidine, and spray it on their Roaches. So, does listerine kill roaches?

Listerine is a popular mouthwash used to fight bad breath and gingivitis. It’s often used to fight halitosis, which is the medical term for bad breath.

However, Listerine isn’t just for fighting bad breath. It’s also used to kill roaches.

Roaches carry bacteria that can contribute to bad breath. Listerine kills these bacteria and the roaches themselves.

When Listerine’s active ingredient, isopropyl alcohol, is applied to a roach’s body, it causes the roach to dehydrate and dry out. Once the roach’s body dehydrates, it dies.

However, Listerine doesn’t work instantly. The roach has to come into contact with the Listerine for it to work.

Furthermore, Listerine only works when it’s sprayed directly on the roach. If you spray the Listerine on a paper towel, it won’t kill the roach.

Finally, Listerine doesn’t kill other insects such as the fly and mosquito.

Does Listerine Kill Roaches?

Listerine is a popular mouthwash brand that is used for bad breath and to treat gingivitis.

However, is it effective for killing roaches? The answer is yes and no.

Listerine contains thymol and eucalyptol, which are both toxic to roaches.

However, if you apply too much Listerine to your roaches, it can lead to respiratory damage and even death.

Therefore, it’s important to use Listerine in moderation and only when necessary.

How to Use Listerine To Kill Roaches?

Mix Water and Listerine

Mix 1 part water to one part diluted liquid version of your mouthwash in a spray bottle. Then, shake the bottle well to mix the ingredients thoroughly.

Before putting the solution in any room of the house where roaches are present, spray the mixture on the affected area and wait for at least 30 minutes to kill all visible bugs.

Pour the Solution Into a Spray Bottle

The next step is to strain the solution from the bottle into a spray bottle by pouring it into a funnel that’s attached to a plastic cup or bowl with a spout.

Pour the solution into the spray bottle and then shake the bottle well to mix the solution with the water in the bottle.

Don’t use a bottle that has a lid because the lid can trap the fumes of the mixture inside and can burn you when you open it after spraying.

It will make your house smell nice, and any odors coming from the cockroaches will be eliminated.

Recognize a Cockroach Nest

The next stage is to locate where the cockroaches are hiding.

You can use a flashlight to find them at night or you can use a bug light. A bug light is a device that emits ultraviolet light that attracts bugs and lures them out from hiding places.

You can also buy sticky traps and place them in areas where you have seen a lot of cockroaches during the day. Then check the traps at night to see how many of the bugs were caught in them.

These traps attract the bugs using a strong adhesive and then trap them until the glue dries out and the roaches fall onto the paper below.

This is significant because Listerine will only kill live roaches, but it will not kill the roach eggs that have already been laid in the wall, under cabinets, etc.

Spray the Mixture

Spray the roaches with a mixture of dish soap and white vinegar.

The results will be immediate; however, this is not a long-term solution as you will need to repeat the procedure again the next day in order to kill the nymphs and adults as well.

How to Use Listerine And Peppermint Oil Spray To Repel Roaches

Combine Listerine and Peppermint Oil in a Bowl.

Take one cup of Listerine and add two drops of peppermint oil to it.

Shake the solution well before using it. Pour it into a spray bottle and shake it again before using it.

If the mixture is not mixed properly before use, it may cause irritation to the skin.

Keep the mixture away from children as it can be dangerous for them if ingested.

3 Cups of Water Should Be Added to the Mixture.

Now, combine 3 cups of warm water to the mixture and mix well to make a spray.

Next, thoroughly shake the spray bottle so that the solution is evenly spread in it.

It will yield a spray of about 2-4 ounces in the bottle after shaking it well.

Fill a Spray Bottle Halfway With This Solution.

Fill a spray container halfway with this solution and fill up the rest with water; this will make the solution last much longer for reuse and help you save on money as well.

It will make it less messy to apply also as the hair will be soaked well by the solution as you apply it on your hair.

Spray the Solution in Many Spots.

Spray Listerine and peppermint oil around the infested areas and other spots where you see signs of cockroaches in the house.

The solution should be sprayed along the edges of floors and walls too, but not on the furniture as it can cause damage if it gets spilled on it.

How Does Listerine Kill Roaches?

Listerine is a disinfectant with antifungal, antiviral, antibacterial properties that make it a good roach killer.

It comprises at least 26 chemicals, however, it is the active component eucalyptol that kills roaches effectively.

Both of these ingredients have antimicrobial properties that kill the germs inside the mouth and also prevent the growth of the bacteria and other germs that lead to infections such as pneumonia, bronchitis, strep throat, etc.

Thymol is an irritant for the nerves of the roaches and renders them unconscious.

When methyl salicylate is consumed orally, it irritates the tissues of the digestive system and renders the roaches unconscious.

The American cockroach’s respiratory system is so sensitive that even a small amount of eucalyptus oil can render them unconscious within a matter of minutes.

The combination of these chemicals provides an effective remedy for killing cockroaches by rendering them unconscious quickly.

How Long Does It Take Listerine To Kill Roaches?

If roaches come into touch with Listerine, they will die immediately due to the high alcohol content in the mouthwash.

You will most likely notice dead roaches everywhere in just a few hours after the treatment; however, it can take as long as a week to get rid of all the adults if you apply the same treatment daily.

Following the first roach eradication, you should continue applying Listerine on a weekly basis until there are no more roaches in your home.

How Does Listerine Keep Cockroaches At Bay?

Several essential oils have natural repellent properties and can keep insects away; one such oil is peppermint oil, which is a natural insecticide.

Its strong smell keeps many insects at bay, including flies, mosquitoes, ants, etc.

It also repels spiders, fleas, ticks, mice, and even cockroaches.

So adding a few drops of peppermint oil to your regular household cleaning product will deter and kill cockroaches as well.

They act as a strong deterrent for cockroaches and other pests and inhibit their breeding activity.

Because roaches dislike the scent, the oils help to keep them away from the home.

They avoid going near houses with this powerful smell as they do not like it; instead, they stay away and search for a different place to breed. Thus, you can get rid of these pests naturally and prevent their infestation in the future as well.

These fragrances are quite overwhelming for roaches, therefore using them regularly will help you keep these insects away from your homes.

Also Read: Does Bleach Kill Roaches?


Listerine kill roaches is a brand of mouthwash that kills germs and bacteria in the mouth.

However, it also kills bugs like roaches and ants. If you spray some listerine on a roach, it will immediately die.

This brings a lot of benefits to consumers. First, it eliminates the annoyance of roach infestations.

Second, it prevents the spread of germs and disease from the roach’s body. Third, it prevents the spread of disease from the roach’s body to other people.

Finally, it prevents roaches from spreading germs and disease to food in your home. Because of these benefits, everyone should use listerine kill roaches regularly in their homes.