The treatment that ends a lice case is a medicine made for head lice, used exactly as the label directs, followed by careful combing and another check about a week later. The American Academy of Pediatrics calls head lice medicine the most effective way to treat lice, and says the comb-out method usually does not get rid of lice on its own. Timing matters as much as the product, because eggs hatch days later. Check with your child’s doctor first, and check everyone in the household the same day.
Is It Lice, or Something That Looks Like Lice?
Proof is a live louse, not a stray speck. Finding a live nymph or adult louse on the scalp or hair is the best way to diagnose an infestation, says the CDC, which also reports that misdiagnosis of head lice is common. Nits get confused with dandruff, hair spray droplets and dirt particles, and the tell is that a nit stays firmly attached to one hair while a flake does not. Lice avoid light and move fast, so a magnifying lens and a fine-toothed comb may help.
- Start at the hairline at the back of the neck and behind the ears, in a bright room, parting the hair one small section at a time.
- Wet the hair, comb each section, wipe the comb on a wet paper towel, and look at what comes off.
- Eggs sit within 4 to 6 mm of the scalp, the AAP says, and do not survive farther away.
What Kills Lice, and What Only Looks Like It Works
Medicine made for head lice is what kills lice, and home remedies are not a substitute. There is no scientific evidence that suffocating head lice with mayonnaise, olive oil, margarine, butter or similar substances works, according to the CDC’s treatment guidance, and the AAP puts petroleum jelly, tub margarine and essential oils in the same group because no studies prove they work. The AAP also warns that gasoline and kerosene are dangerous and flammable, and that placing anything made of plastic on a child’s head is dangerous.
Lice medicine should be used only when it is certain a child has living head lice, the AAP says. Both over-the-counter and prescription medicines treat head lice, and the CDC says they are generally safe and effective when used correctly. The AAP adds that over-the-counter treatments sometimes are not the most effective, because lice can be resistant to their active ingredients in some communities. Its advice is to call your pediatrician before treatment, and deciding whether you need a prescription lice treatment belongs in that conversation.
Then follow the label exactly. An adult applies the medicine, children never apply it themselves, and no child is left alone with medicine in their hair. The AAP says to rinse it off over a sink with warm water rather than hot. One CDC detail trips families up: do not use a combination shampoo/conditioner, or conditioner, before using lice medicine.
Why the Next Two Weeks Decide Whether Lice Come Back
Lice can come back when eggs that a first treatment did not kill hatch and nobody is watching for them. Whether a second treatment is needed depends on the product: some medicines kill lice and eggs, and some kill lice but not eggs, in which case the CDC says to treat again about a week after the first treatment, 7 to 9 days depending on the drug. The AAP reports a second treatment at 7 to 9 days if live lice are seen, and says to check with your child’s doctor before beginning a second or third medicine.
| After treatment | What the CDC and the AAP say |
|---|---|
| 8 to 12 hours | A few lice still moving slowly do not need another application. |
| 1 to 2 days | Do not re-wash the hair after removing the medicine. |
| Every 2 to 3 days, for 2 to 3 weeks | Comb out nits and lice. |
| About 7 to 9 days | Treat again if the medicine does not kill eggs. |
| Live lice days later | Talk to a healthcare provider before re-treating; they may suggest a different medicine. |
The CDC lists misdiagnosis, recent conditioner, not following instructions, resistance and reinfestation among the reasons a treatment fails, and says not to treat one person more than 2 to 3 times with the same medication when it is not working. If the lice seem as active as before, the medicine may not be working, so talk to a healthcare provider rather than adding a second product. When a case drags on, it helps to know why lice treatment fails and how often to comb after treatment.
Who Else at Home Needs a Check
Everyone at home gets checked, and the CDC says to treat all infested people and anyone they share a bed with at the same time. A quiet case is easy to miss, because people with head lice may not have symptoms, particularly with a first or light infestation. The CDC says head lice spread mainly by direct contact with the hair of a person who has lice; they crawl, and cannot hop or fly. The AAP says regular checks are a good way to spot head lice before they have time to multiply, which is the argument for checking the whole family on one day instead of one head at a time.
- Teach children to avoid hair-to-hair contact during play.
- Do not share hats, scarves, coats, hair ribbons or barrettes.
- Do not share combs, brushes or towels.
Laundry, Beds and the Rest of the House
Heads come first, and the house needs little. The CDC says spending much time and money on housecleaning activities is not necessary to avoid reinfestation, and that lice die within two days if they fall off a person and cannot feed. Do not use fumigant sprays or fogs, which the CDC says are not necessary and can be toxic if inhaled or absorbed through the skin, and the AAP says not to spray pesticides in your home.
- Machine wash and dry clothing, towels and bed linens used in the two days before treatment, on the hot water cycle at 130 degrees Fahrenheit with high heat drying.
- Seal what you cannot wash in a plastic bag for two weeks; the AAP says you do not need to throw these items away.
- Soak combs and brushes in hot water of at least 130 degrees Fahrenheit for 5 to 10 minutes.
- Vacuum the floor and furniture where the person sat or lay.
Frequently Asked Questions
How soon does itching start?
Itching can take four to six weeks to appear the first time a person has head lice, the CDC says. It is an allergic reaction to louse bites, and the CDC calls itching the most common symptom, along with a tickling feeling, irritability and sleeplessness. Checking beats waiting for a scratch, since the itch can lag the case by weeks.
Why does the scalp still itch after treatment?
Itching caused by head lice can last for weeks, even after the lice are gone, the AAP says. Some medicines can also cause itching or a mild burning sensation. The signal that matters is live, crawling lice several days later, not the itch itself; why a head still itches after lice treatment walks through the difference.
Do all the nits have to come out?
Nits may stay in the hair after treatment, and the CDC says successful treatment will kill crawling lice. Nits attached more than 1/4 inch from the base of the hair shaft are almost always hatched or dead, the CDC says. The AAP notes that some prescription products do not call for nit combing.
Can lice spread in a swimming pool?
Head lice are unlikely to spread in a swimming pool, the CDC says, and chlorine levels in pool water do not kill them. Lice can survive under water for several hours, so a swim is neither a treatment nor a reason to worry. A shared towel is the item to keep separate, since the CDC lists infested combs, brushes and towels among the less common ways lice spread.
Can the family pet carry lice?
Animals do not get or spread head lice, the CDC says, so the dog and cat are not part of the problem. One pet item does help: the CDC says flea combs made for cats and dogs are also effective for combing. Never use a medicine made for animals on a person, which the AAP warns against.
Does a lice case mean we are not clean enough?
A lice case says nothing about how clean a home or a head is. Getting head lice is not related to cleanliness of you or your environment, the CDC says, and MedlinePlus agrees that personal hygiene and cleanliness have nothing to do with getting head lice. The CDC estimates 6 to 12 million infestations each year in the United States among children 3 to 11 years of age.
How We Help Families End a Lice Case
When a head check at home leaves you unsure, or when a case has outlasted two rounds of combing, our clinic can take it from there. We check the whole family, because one missed head restarts the cycle. Treatment is non-toxic and finished in one visit, and our 30 Day Guarantee applies when the whole family is checked. You can read how our professional lice treatment works before you decide, and same-day appointments are available when a case is in front of you right now. Bring what you have already tried, and the questions your pediatrician raised. When you are ready, book a head check with Lice Lifters of Mercer County.
