Head lice treatments compared: what actually works in 2026
Store shampoos, prescriptions, heated air, combing, mayonnaise. Here's what published studies and the FDA, CDC and American Academy of Pediatrics say about each, with links to the sources so you can check for yourself.
A note on bias: we're a lice treatment company, and our own treatment uses heated air and combing. We've tried to report every option fairly, including where the evidence for heated air comes from. This page is general information, not medical advice. Ask your pediatrician what's right for your child.
- The classic store shampoos often fail now. Lice from 48 states carry genetic resistance to pyrethrins and permethrin (the ingredients in RID and Nix) at very high rates: about 98% on average across the sites tested.
- Ivermectin lotion (Sklice) is now over the counter. The FDA moved it off prescription in 2020. It's one 10-minute application for ages 6 months and up.
- Prescription spinosad (Natroba) kills eggs too, and in trials beat permethrin by roughly 85% to 44%.
- Heated air kills eggs without chemicals, but the studies come from the team that invented the device.
- Mayonnaise, olive oil and butter don't work in lab tests, and the AAP advises against them.
“Lice-free” was measured on different days in different trials, so compare rows loosely. Numbers in brackets match the sources below.
| Option | How you get it | Ages | Treatments | What the evidence shows |
|---|---|---|---|---|
| Pyrethrins (RID, A-200) | Over the counter | 2 years+ | 2 (second on day 9–10) | Doesn't kill eggs. Resistance mutations in about 98% of US lice tested [1][3]. |
| Permethrin 1% (Nix) | Over the counter | 2 months+ | 2 | 43–45% lice-free in US trials (2009); 55% in a Florida trial [4][7]. |
| Ivermectin 0.5% lotion (Sklice) | Over the counter since 2020 | 6 months+ | 1 (10 minutes, no combing) | 95% lice-free on day 2, 85% on day 8, 74% on day 15, versus 18–31% for a placebo lotion [5][6]. |
| Spinosad 0.9% (Natroba) | Prescription | 6 months+ | 1 (repeat only if live lice at day 7) | 85–87% lice-free two weeks after treatment versus 43–45% for permethrin. Kills eggs [4]. |
| Malathion 0.5% | Prescription | 6 years+ | 1–2 (left on 8–12 hours) | 90% free of live lice at day 7 in label trials. Flammable while wet [2][7]. |
| Oral ivermectin | Prescription, off-label for lice | 33 lb+, not in pregnancy | 2 | 95% lice-free versus 85% for malathion in hard-to-treat cases [2][8]. |
| Heated air (LouseBuster device) | Professional treatment | 4 years+ (FDA clearance) | 1 (about 30 minutes) | Killed nearly 100% of eggs and 80% of hatched lice; 94.8% combined in a later study. Both studies by the device's inventors [9][10]. |
| Wet combing | Any fine metal lice comb | Any | Every 3–4 days for 2+ weeks | Mixed: 38% cured in one UK trial, 57% in another. Depends on how thorough the combing is [11][12]. |
| Dimethicone (silicone lotion) | Over the counter | Varies by product | 2, a week apart | 69–97% cured in European and Brazilian trials. Works physically, so resistance shouldn't matter [13][14]. |
| Mayonnaise, olive oil, butter, vinegar | Home remedy | — | — | Didn't control lice in lab tests; none stopped egg-laying. AAP advises against [15][16]. |
Benzyl alcohol (Ulesfia) and abametapir (Xeglyze) were FDA-approved but are now discontinued, so they're left out.
A 2016 study tested lice from 138 sites in 48 states for “knockdown resistance” mutations, the genetic change that lets lice survive pyrethrins and permethrin. At 132 of the 138 sites, every louse tested carried them [3]. That's the “super lice” you may have read about. CDC still lists these products as options and notes that resistance varies by place [1]. If you use one and still see live, moving lice a day or two later, it isn't working for your family. Don't keep repeating it.
Ivermectin lotion (Sklice and store brands) is now sold over the counter: one 10-minute application on dry hair, no combing required [5][6]. Spinosad (Natroba) needs a prescription, kills eggs as well as lice, and usually takes one treatment [4]. Both did much better than permethrin in their trials. Those trials were funded by the manufacturers, as most drug-approval trials are.
A 2006 study in Pediatrics tested six ways of blowing heated air through infested hair. The best, a purpose-built device later cleared by the FDA as the LouseBuster, killed nearly all eggs and 80% of hatched lice in one 30-minute session, with no side effects [9]. A 2011 follow-up found 94.8% of lice and eggs killed [10]. Heat dries lice out rather than poisoning them, so resistance is unlikely. Both studies come from the University of Utah team that invented the device. That's the method we use, followed by a full comb-out.
Combing wet, conditioned hair with a fine metal comb works when it's done thoroughly and often enough, but the trials show how hard that is at home: 38% cured in one study, 57% in another [11][12]. Whatever else you use, combing every two to three days for two to three weeks catches what treatment misses [1].
In lab tests, vinegar, rubbing alcohol, olive oil, mayonnaise and melted butter didn't control lice, and none stopped them laying eggs. Lice survived hours under water [16]. The AAP advises against these and against essential oils, and warns never to use gasoline or kerosene [15].
CDC's advice is modest: wash bedding and clothes used in the two days before treatment in hot water and dry them on high heat, bag anything you can't wash for two weeks, soak brushes in hot water, and vacuum. Don't use fumigant sprays or foggers. Pets don't spread head lice [17].
Our clinics in SE Portland and Beaverton, and our in-home technicians across the metro, treat with heated air and a full comb-out, usually in one visit, with a 60-day guarantee. Call 971-771-3270, 7am–8pm, 7 days a week.
- CDC. Clinical Care of Head Lice. cdc.gov
- FDA. Drugs@FDA listings for Ovide/malathion (NDA 018613, ANDA 091559); Ovide prescribing information on DailyMed.
- Gellatly KJ et al. Expansion of the knockdown resistance frequency map for human head lice in the United States. J Med Entomol 2016;53(3):653–9. Full text
- Stough D et al. Efficacy and safety of spinosad and permethrin creme rinses for head lice. Pediatrics 2009;124(3):e389–95. PubMed
- Pariser DM et al. Topical 0.5% ivermectin lotion for treatment of head lice. N Engl J Med 2012;367:1687–93. PubMed
- FDA. Drugs@FDA, Sklice (NDA 202736): over-the-counter, approved October 27, 2020. accessdata.fda.gov
- Meinking TL et al. Efficacy of a reduced application time of Ovide lotion compared to Nix creme rinse. Pediatr Dermatol 2004;21(6):670–4. PubMed
- Chosidow O et al. Oral ivermectin versus malathion lotion for difficult-to-treat head lice. N Engl J Med 2010;362:896–905. PubMed
- Goates BM et al. An effective nonchemical treatment for head lice: a lot of hot air. Pediatrics 2006;118(5):1962–70. PubMed
- Bush SE et al. Efficacy of the LouseBuster, a new medical device for treating head lice. J Med Entomol 2011;48(1):67–72. PubMed
- Roberts RJ et al. Comparison of wet combing with malathion for treatment of head lice in the UK. Lancet 2000;356:540–4. PubMed
- Hill N et al. Bug Buster kit versus over-the-counter pediculicides. BMJ 2005;331:384–7. PubMed
- Burgess IF et al. Treatment of head louse infestation with 4% dimeticone lotion. BMJ 2005;330:1423. PubMed
- Heukelbach J et al. A highly efficacious pediculicide based on dimeticone. BMC Infect Dis 2008;8:115. PubMed
- American Academy of Pediatrics. Head Lice: What Parents Need to Know. HealthyChildren.org
- Takano-Lee M et al. Home remedies to control head lice. J Pediatr Nurs 2004;19(6):393–8. PubMed
- CDC. Treatment of Head Lice. cdc.gov
Last reviewed October 2026.