Treating and Preventing Head Lice: Practical, Up-to-Date Steps

Head lice are scalp parasites that spread mainly by head-to-head contact. Effective control uses approved topical or prescription treatments and/or careful wet combing, combined with repeat care at 7-10 days to address eggs. Wash bedding and washable items in hot water and dry on high; seal nonwashable items for two weeks. Routine vacuuming suffices; avoid fumigation. Check local school policy and see a clinician for persistent problems or treatment concerns.

What head lice are

Head lice (Pediculus humanus capitis) are tiny, wingless insects that live on the scalp and feed on blood. They spread mainly by direct head-to-head contact, most often among preschool and elementary-age children. Lice cause itching for some people, but they are not a sign of poor hygiene and do not transmit disease.

Effective medical treatments

Over-the-counter (OTC) products that contain 1% permethrin (e.g., Nix) or pyrethrins with piperonyl butoxide remain common first-line options. In many areas lice have developed resistance to permethrin and pyrethrins, so follow-up is important if live lice persist.

Prescription options include malathion 0.5% lotion, benzyl alcohol 5% lotion, and topical ivermectin 0.5% lotion. Oral ivermectin may be used off-label in certain situations. Always follow dosing instructions and check with your pediatrician or dermatologist before using prescription therapies on young children.

Non-chemical option: wet combing

Wet combing (careful work with a fine-tooth nit comb on wet, conditioned hair) is an effective, chemical-free method. Perform combing every 2-3 days for at least two weeks to catch newly hatched lice before they mature.

Eggs (nits) and why repeat care matters

Lice eggs are glued to the hair shaft and are harder to kill than active lice. Many treatments kill live lice but not all eggs. For that reason, most guidance recommends repeating the chosen treatment or continuing combing 7-10 days after the first application to remove newly hatched lice before they lay eggs.

What to do at home: washing, items, and cleaning

Wash recently worn clothing, hats, bedding, and towels in hot water (130°F/54°C or hotter) and dry on high heat for 20+ minutes. Items that cannot be washed can be sealed in a plastic bag for 2 weeks to ensure lice die off. Soak combs and brushes in hot water (at least 130°F) for 5-10 minutes.

Routine household cleaning (vacuuming floors and furniture) is sufficient. Avoid fumigant sprays or professional extermination; these are unnecessary and can be hazardous.

School, exclusion, and when to see a clinician

Many public health authorities advise against excluding children from school for nits alone. Policies vary by district, so check with your school. See a clinician if OTC treatment fails, you find live lice after repeated treatment, the child is very young, or you suspect secondary skin infection from scratching.

Practical checklist

• Confirm live lice before treating.

• Use an appropriate product or wet combing method.

• Repeat treatment or combing at 7-10 days.

• Wash and dry bedding and clothes on hot settings or seal for 2 weeks.

• Avoid home fumigation products.

• Contact a healthcare provider for persistent infestations or questions.