Head lice are treatable at home with a combination of medicated products and thorough combing. Most cases clear up within two to three weeks when you follow the right steps and stick to the timeline. The key is choosing an effective treatment, removing lice and eggs manually, and repeating the process to catch any newly hatched nymphs before they can lay more eggs.
Start With an Over-the-Counter Lice Shampoo
The most common first-line treatments are shampoos containing permethrin (1%) or pyrethrins, both available without a prescription at any pharmacy. You apply the product to damp hair, leave it on for the time specified on the label (usually about 10 minutes), then rinse it out. These treatments kill live lice on contact but don’t reliably kill all eggs, which is why a second application is necessary.
There’s a catch: lice in many areas have developed some degree of resistance to these ingredients. The CDC acknowledges this resistance exists but notes its exact prevalence hasn’t been well studied. In practical terms, this means the shampoo might not kill every louse on the first try. If you’re still finding live lice two or three days after treatment, the product likely isn’t working and you’ll need a stronger option from your doctor.
Why You Need a Second Treatment
Lice eggs (nits) take about a week to hatch. Most OTC treatments don’t kill eggs, so any survivors will produce a new generation of tiny nymphs days after your first application. That’s why a second treatment 7 to 9 days after the first is standard. This window is timed to kill newly hatched lice before they’re old enough to start laying eggs themselves. Skipping the second round is one of the most common reasons lice come back.
The Wet Combing Method
Manual removal with a fine-toothed lice comb is just as important as any medicated product. A proper lice comb has teeth spaced less than 0.3 mm apart, narrow enough to trap both adult lice and nymphs. Metal combs tend to work better than plastic ones because the teeth don’t flex.
Here’s how to do it effectively:
- Wash hair with regular shampoo, then apply a generous amount of conditioner. The conditioner makes the hair slippery, which stuns lice and makes them easier to comb out.
- Use a wide-toothed comb first to detangle completely.
- Switch to the lice comb. Slot the teeth into the hair right at the roots, with the comb lightly touching the scalp, and draw it all the way down to the tips.
- After each stroke, check the comb and wipe or rinse off anything you find.
- Work through the entire head section by section. This takes about 10 minutes for short hair and up to 30 minutes for longer hair.
- Rinse out the conditioner, then comb through one more time to catch anything you missed.
Repeat this combing session every three days. You’re done when you’ve had four consecutive sessions with no lice found. That pattern of repeated checks is what confirms the infestation is actually gone, not just temporarily reduced.
What About Home Remedies?
Tea tree oil, mayonnaise, olive oil, neem oil, vinegar, and saline spray are all popular suggestions online. None of them are supported by scientific evidence. Johns Hopkins Medicine describes these approaches as “messy, time consuming” and ineffective. The theory behind slathering hair in mayonnaise or oil is that it suffocates lice, but lice can survive for hours with limited airflow, and eggs are completely unaffected. You’re better off spending that time on thorough wet combing, which has actual clinical data behind it.
When OTC Products Don’t Work
If you’ve completed two rounds of OTC treatment plus consistent combing and you’re still finding live lice, resistance is the likely culprit. Your doctor can prescribe stronger topical treatments that work through different mechanisms than the drugstore options. These are still applied at home in most cases. Some prescription formulas are designed to kill both lice and eggs in a single application, which simplifies the process considerably. Your doctor will recommend the right option based on your child’s age and the severity of the infestation.
Cleaning Your Home
Lice can’t survive long off the human scalp, so you don’t need to deep-clean your entire house. Focus on items that touched the infested person’s head in the two days before treatment started.
- Clothing, bedding, and towels: Machine wash in hot water (130°F) and dry on high heat.
- Items you can’t wash: Seal them in a plastic bag for two weeks. Any lice or nits trapped inside will die without a human host.
- Combs and brushes: Soak in hot water (at least 130°F) for 5 to 10 minutes.
You don’t need to bag up every stuffed animal in the house or spray furniture with pesticides. Lice spread through direct head-to-head contact, not from sitting on a couch. Vacuuming furniture and car seats where the person’s head rested is a reasonable precaution, but it’s not where most reinfestation comes from. Reinfestations almost always happen because eggs on the scalp survived treatment or because the person had head-to-head contact with someone else who still had lice.
Checking the Whole Family
If one person in the household has lice, check everyone else. Use the wet combing method on each family member. Only treat people who actually have live lice or viable eggs. Preventive treatment of people who aren’t infested isn’t recommended because it contributes to resistance without providing any benefit. Keep checking household members every few days during the treatment period to catch any new cases early.