Listerine Lice Treatment: Why It Doesn’t Work

Listerine Lice Treatment: Why It Doesn’t Work

Oct 17, 2023Maria Jaworski

First of all, don’t use Listerine as a treatment for lice. Just don’t. It may be an appealing alternative due to its price when compared to the price of lice shampoos and treatments, but that’s because it’s not a lice shampoo. To be classified as a lice treatment, products must go through extensive testing by the FDA and other regulatory agencies, submitted in clinical trials, and proven to be consistently effective. Listerine has not done that. It is a mouthwash, not a lice shampoo.

The Ingredients

Listerine Hair Fairies Nit-Zapping™ Clenz Shampoo
Active ingredient: Alcohol (30%) Active ingredient: Cyclomethicone
Other ingredients: Eucalyptol, Thymol, Menthol, Methyl Salicylate Other ingredients:: Tea Tree Oil, Extracts of Lemongrass, Witch Hazel, Aloe Vera, Arnica, Chamomile, Cucumber, Linden, Marshmallow Root, Nettle, Rose Hips, Fennel, Clary Sage

Suffocation vs. Dehydration

The reason Listerine doesn’t work to eliminate lice is that different chemicals treat lice differently. The active ingredient in Listerine is alcohol, and alcohol-based alternative lice treatments (like Listerine) predominantly rely on suffocation to eliminate lice. This is a good step, but far from an effective, permanent solution. Head lice in the egg stage have a protective, waxy coating that acts as a waterproofing agent and allows them to continue their evolution into live nits. (While Listerine may loosen some of the eggs, it’s not enough.) The alcohol in Listerine deprives the eggs of oxygen in order to suffocate them; however, it can take 8-24 hours for suffocation to occur. In that time, the lice eggs can lie dormant and the Listerine wears off. As a result, the affected party will need almost constant Listerine treatments over the course of several days to ensure the lice eggs don’t hatch. In addition, any live nits and eggs will still have to be combed out with a special lice comb.


Why, then, do some people swear by Listerine? The secret may be more in the act than in the ingredients. Many articles that identify this particular method as a solution also call for the use of a lice comb and vinegar. It is more likely the act of combing out the lice with a lice comb, combined with the vinegar, that eliminates the lice more than the active ingredients in Listerine themselves. Remember those breakfast cereal commercials on Saturday mornings for Apple Jacks that said “part of this complete breakfast,” then showed the sugary cereal alongside four apples, three bananas, two eggs, and a grapefruit? You got the feeling the cereal wasn’t really the main contributor to the “complete” part of the meal. The Apple Jacks are in there somewhere… When it comes to lice treatment, Listerine is much the same as Apple Jacks. It may work as “part of the complete breakfast,” but it is not the key ingredient, or even beneficial to the lice treatment diet. In much the same way the fruit and veggies end up doing most of the work to make up the complete breakfast for the sugary cereal, the lice comb bears the bulk of the responsibility for delivering results on behalf of the Listerine. Cyclomethicone, the active ingredient in Hair Fairies Nit-Zapping™ Clenz Shampoo, is a fast-acting dehydrating agent that does not rely on suffocation. It actively dehydrates the eggs on contact, dissolves the protective coating, and attacks lice instantly. In addition, Hair Fairies shampoo has replenishing ingredients to restore nutrients to the hair. Listerine has none of those things, and can potentially do a lot of damage to your scalp unless it is diluted properly. Questions? Hair Fairies is always here to help! Get in touch.

Insult to Injury

For those of us who like the taste of mayonnaise, there has to be merit to the idea of not wanting to associate something you like (delicious mayo) with something you don’t (head lice). Do you really want to think about head lice every time you make a sandwich for the rest of your life? Also, there is that little problem with potentially giving your child food poisoning. Mayonnaise left out for more than a couple of hours turns rancid. If one of those strands of hair on your child’s head is accidentally consumed, now you have a child with lice and food poisoning. Fun! Speaking of Suffocation… Keeping the mayonnaise on the head requires some form of cap or head covering. Consider that your child will likely need to wear something like that to bed — not a safe situation. In fact, in February 2015, an 18-month-old child suffocated during treatment: “Sgt. John Delaney says the little girl’s scalp was covered in mayonnaise and a plastic shopping bag was placed over her head, a common home remedy for head lice. The girl was left unattended and apparently fell asleep, allowing the bag to slip down over her face, suffocating her.”

The Hair Fairies Difference

The Hair Fairies experience is geared toward making your entire experience LESS stressful, not more. Our salons are clean and kid-friendly; you come in with lice, you leave without it. No muss, no fuss. If you must… If you feel you have no other options and really want to use the mayonnaise method, we have provided a handy 5-step guide for your convenience:

5-Step Guide for Mayonnaise LiceTreatment


  1. Retrieve mayonnaise from the fridge
  2. Make a sandwich
  3. Return mayonnaise to the fridge
  4. Eat the sandwich
  5. Head to Hair Fairies for proper treatment


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