The Bottom Line

Head lice are a very common problem — affecting 3–10% of school-age children in developed countries — and have nothing to do with poor hygiene. Lice spread through direct head-to-head contact. Effective treatments are available, and your child can return to school after treatment begins. Check all household members, treat those who are infested, and wash bedding and clothing in hot water. Don't panic — this is manageable.

What Are Head Lice?

Head lice (scientific name: Pediculus humanus capitis) are tiny wingless insects that live on the human scalp. Adult lice are about 2–3 millimeters long — roughly the size of a sesame seed. They feed on small amounts of blood from the scalp multiple times a day and can only survive a few days without a human host.

Lice lay eggs called nits. Each nit is glued tightly to a hair shaft near the scalp, appears tan to white, and is about 1 millimeter long — smaller than a sesame seed. Nits hatch in 7–10 days, and the resulting nymphs mature into adults in another 10–14 days. Adult lice live 3–4 weeks on the host.

Head lice are not a sign of dirty hair or poor hygiene. They affect children across all social and economic backgrounds.

Signs Your Child May Have Head Lice

  • Itching of the scalp — often the first complaint, sometimes intense enough to disturb sleep
  • Feeling of something moving in the hair
  • Visible nits — tiny tan or white ovals firmly stuck to hair shafts, especially near the nape of the neck and behind the ears
  • Visible live lice — small, dark, fast-moving insects on the scalp or hair
  • Scratch marks or sores on the scalp from scratching (secondary bacterial infection is possible)

How to tell nits from dandruff: dandruff flakes brush off easily. Nits are firmly cemented to the hair shaft and won't move when you blow on them or slide your fingers along the hair.

How Do Children Get Head Lice?

Lice spread almost exclusively through direct head-to-head contact with an infested person. This happens easily during play, sleepovers, sports, and school activities where children's heads are close together. Sharing combs, hats, helmets, or hair ties is a less common but possible route. Lice cannot jump or fly — they can only crawl.

Treatment Options

Multiple effective treatments are available. Treating all infested household members at the same time is important to prevent re-infestation.

First-Line Treatments (Available Over the Counter)

  • Permethrin 1% cream rinse (Nix): Applied to damp hair, left on for 10 minutes, then rinsed out. A second treatment 7–10 days later is needed to kill lice that hatch from any surviving eggs.
  • Pyrethrins + piperonyl butoxide (Rid, A-200): A plant-derived treatment applied similarly. Less effective against eggs, so repeat treatment is essential.

Prescription Treatments (for Resistant Lice)

  • Malathion lotion: An organophosphate that kills both lice and many eggs. Left on for 8–12 hours. Not for children under 6.
  • Spinosad (Natroba): A newer treatment effective in a single application for most children.
  • Ivermectin lotion (Sklice): Applied once and left on for 10 minutes.
  • Benzyl alcohol lotion (Ulesfia): Kills lice by suffocation.

Manual Removal (Nit Combing)

After any treatment, use a fine-toothed nit comb on wet, conditioned hair to remove dead lice and nits. Comb from the scalp outward, section by section. This step improves results significantly.

What About Home Remedies?

Tea tree oil, mayonnaise, and other home remedies have no reliable scientific evidence behind them. Stick with proven treatments to clear lice quickly and protect your child from prolonged infestation.

Household and School Steps

  • Wash all bedding, clothing, and towels in hot water (at least 130°F / 54°C) and dry on high heat
  • Soak combs and brushes in hot water for 10 minutes
  • Vacuum upholstered furniture and car seats
  • Items that can't be washed can be sealed in a plastic bag for 2 weeks
  • Notify your child's school so other parents can check their children
  • Your child can return to school once treatment has been applied

When to See a Dermatologist

  • Lice persist after two rounds of over-the-counter treatment — resistance is increasingly common in some areas
  • Your child's scalp has signs of bacterial infection (increasing redness, crusting, swelling, or fever)
  • You are unsure if what you are seeing are nits or something else
  • The infestation keeps coming back despite thorough treatment

Frequently Asked Questions

Does my child have to stay home from school?

Most major health organizations, including the American Academy of Pediatrics, no longer recommend keeping children home from school once treatment has started. "No nit" policies are considered outdated. Check with your school's specific policy.

Can lice spread disease?

In developed countries, head lice are not known to spread any disease. The main health concerns are the intense itching and potential skin infections from scratching.

How did my child get lice if they have clean hair?

Lice actually prefer clean hair — it's easier to grip. Hygiene has nothing to do with lice infestation. They spread through head-to-head contact, period.

Will lice go away on their own?

No. Lice will not go away without treatment. Each female louse lays about 6–10 eggs per day, so an untreated infestation grows quickly. Treatment should begin as soon as lice or nits are confirmed.

References

  1. Paller AS, Mancini AJ. Hurwitz Clinical Pediatric Dermatology. 5th ed. Elsevier; 2016.
  2. Habif TP. Clinical Dermatology: A Color Guide to Diagnosis and Therapy. 6th ed. Elsevier; 2016.
  3. Burgess IF, Brunton ER, Burgess NA. Insecticide resistance in human head lice. Pest Manag Sci. 2013;69(2):213-220.
  4. Jones KA, Baqai F. Systematic review and meta-analysis of the efficacy of pediculicides for the treatment of human head lice. Int J Dermatol. 2016;55(4):423-430.
  5. Meinking TL, Vicaria M, Eyerdam WH, et al. Efficacy of a quaternary ammonium compound pediculicide compared to permethrin. Arch Dermatol. 2002;138(2):220-224.

Trusted Resources

Always consult a board-certified dermatologist or your child's pediatrician if over-the-counter treatments are not working or if you have concerns about your child's scalp health.