Answer: Probably Not
We viewed the evidence and read the testimonials to see if Listerine can be used as a mosquito repellent or a mosquito killer.
Summary of Scientific Research
Listerine is often referred to as a cheap, homemade alternative to commercial repellent products due to it containing eucalyptol, a chemical that is heavily used for commercial repellents. However, these commercial repellents tend to use a 75% compound combination of eucalyptol, whereas Listerine tends to only use 1%(1, 2).
This low concentration is made less effective with the water and alcohol that it’s mixed with. Overall, Listerine, if effective, will only be effective for a very short time before wearing off(2), making it a less-than-stellar choice for serious repelling.
There are many, many websites that spread the rumor of Listerine being a good repellent for mosquitoes and other bugs, but these claims are unfounded(3). The rumor started in the early 2000’s with a random chain email that got spread around the world(4), and somehow, this chain email became a staple of bored local news stations.
However, Listerine could, theoretically, be used as low-grade repellent for a very short amount of time, as that 1% eucalyptol may have some effect. However, the alcohol and water will cause it to evaporate shortly after applying. At best, you’re looking at a good 30-40 minutes of outside work before needing to reapply.
If you can, definitely jump for a commercial repellent or any other DIY method, but I don’t recommend Listerine. You want something that will not only last a long time, but will also do a good job of repelling mosquitoes. Listerine has no evidence of being as effective as other DIY counterparts like vinegar or lemon balm, and Listerine definitely can’t compete with DEET products.
Where to Get Listerine
- Liquid – Listerine is available in most stores in some form, either as mouthwash or toothpaste. Wherever you get your hygienic products is where you’ll find a bottle of Listerine. However, you’re going to have more use using it as actual mouthwash than a repellent.
- Sources claim to find yourself an original bottle of Listerine. No, not the blue one! The yellow bottles of Listerine, as these are free of bleaching agents that reduce its ability to repel mosquitoes(5).
- Once you have the liquid bottle, fill a spray bottle with the Listerine. After you fill the bottle, spray the Listerine on surfaces you want mosquitoes to stay away from. Don’t spray yourself with it!
- Homemade Spray – If you are committed to using Listerine as a mosquito repellent, you can mix it with a couple of other ingredients to create an ok repellent.
- The combination is a bit strange, requiring:
- Stale beer
- Epsom salt
- The combination is a bit strange, requiring:
- The goal is to create a concoction similar to weed killer(6). All you need to do is combine equal parts of each ingredient, mix them, then add yeast for every gallon of the concoction. Then voila! You have your ok-ish mosquito repellent. Do the same as you would with the Listerine-only spray.
While I made it clear that Listerine shouldn’t be your go-to, it’s ok for short trips outside or temporary exposure to mosquitoes. However, if you’re in an area that is absolutely infested with mosquitoes, Listerine won’t be effective. Actually, it would be about as effective as a BB gun to a kevlar vest.
On the plus side, you’ll at least be able to freshen up your breath if it doesn’t repel the mosquitoes.
1 – insecthobbyist.com – “The idea of having Listerine as a mosquito repellent sound like a dream for any homeowner; However, eucalyptol usually has a 75% compound concentration, while Listerine only contains below 1%. Let’s not forget that Listerine has other ingredients as well, such as water and alcohol. Due to this, it has the tendency of evaporating quickly.”
2 – nytimes.com – “Several studies, including one by the London School of Hygiene and Tropical Medicine, have found that eucalyptus-based repellents can be extremely effective, and nontoxic to humans. But they often contain the compound in concentrations as high as 75 percent; the concentration in mouthwash is usually below 1 percent. Mouthwashes also contain water and alcohol, so they tend to evaporate quickly.”
3 – thriftyfun.com – “The best and least toxic way to rid your outdoor area of nasty mosquitoes is with Listerine (the original Amber colored kind.) Simply pour the Listerine into a spray bottle and spray the porch, deck or the area around where people hang out.”
4 – liveabout.com – “…Viral message circulating via email and social media claims spraying an outside area with Listerine mouthwash repels and/or kills every mosquito in the vicinity.”
5 – hunker.com – “Fill a spray bottle with one cup of Listerine. Original yellow Listerine works best for this; avoid generic versions with bleaching agents. Listerine can be found at drug stores and supermarkets.”
6 – doityourself.com – “Combine in the container equal parts stale beer, epsom (or sea) salt, and Listerine (or other mouthwash). Then, add a half package of yeast for every gallon of beer mixture. Shake well and allow to sit, stirring occasionally, until the salt and yeast have dissolved into the mixture.”
Other Household Items as Mosquito Repellents
Checkout our analysis of other household items as natural mosquito repellents: