OTC shampoos contain a chemical called pyrethrin (or the synthetic version permethrin) which is toxic to head lice. Pyrethrin can cause side effects such as itching and scalp redness. [3] X Trustworthy Source MedlinePlus Collection of medical information sourced from the US National Library of Medicine Go to source Wash your hair or your child’s hair with this shampoo. Leave it on as long as the label instructs, and do not use conditioner. [4] X Research source Some people find rinsing hair with white vinegar after washing helps the treatment work faster. You will usually need a second treatment 7-10 days after the first shampooing to remove any new lice that hatch. [5] X Research source

Benzyl alcohol (Ulesfia) is considered safe for children older than 6 months, but it may cause scalp redness or itching. In infants, however, it may cause seizures. [6] X Trustworthy Source Centers for Disease Control and Prevention Main public health institute for the US, run by the Dept. of Health and Human Services Go to source Malathion (Ovide) is a leave-in treatment that can be used on people age six and older. Do not use this drug with a hair dryer or near fire—it’s flammable. [7] X Trustworthy Source Centers for Disease Control and Prevention Main public health institute for the US, run by the Dept. of Health and Human Services Go to source Lindane can have severe side effects and isn’t appropriate for all patients, so it’s only used in certain cases when other treatments have failed. [8] X Trustworthy Source MedlinePlus Collection of medical information sourced from the US National Library of Medicine Go to source Rarely, your doctor may prescribe ivermectin, which can be applied topically (Sklice) or given orally. [9] X Research source

Adult or baby lice are between 1/10 and 1/8 inch long. They’re usually gray or tan in color. They cannot fly or jump, but do crawl quickly. [10] X Trustworthy Source Centers for Disease Control and Prevention Main public health institute for the US, run by the Dept. of Health and Human Services Go to source Lice eggs, or nits, are small and coffee-colored. They can be difficult to remove as they’re glued securely to the hair shaft. Empty nits are usually white or clear-colored. [11] X Research source Use a magnifying glass to help you find lice eggs. [12] X Research source

Comb through one section of hair at a time. Start at the scalp and pull the comb flat against the head. Go slowly, and watch for lice and nits as you comb. If you notice any lice and debris build up on the comb, dip it in a bowl of soapy water to remove it.

Continue to wet comb once a week for three weeks, checking for lice. Contact your doctor if you see live lice after three weeks.

Some people are allergic to tea tree oil, so talk to your doctor or test a small amount on your skin for several days before using it. Be especially careful if you’re treating a child. Before bed, sprinkle a few drops of tea tree oil on your scalp. Put a towel on your pillow and go to sleep, leaving the oil in overnight. In the morning, comb your hair to remove any dead lice or eggs. Then, wash and condition your hair—ideally, with products containing at least 2% tea tree oil. [16] X Trustworthy Source PubMed Central Journal archive from the U. S. National Institutes of Health Go to source Repeat as necessary. The process may take a few tries before it works.

For instance, you might apply olive oil, mayonnaise, petroleum jelly, or butter to your hair. Cover your head with a shower cap overnight, then wash your hair in the morning.

Using conditioner with medicated shampoo can prevent treatment from working successfully. Conditioner can act as a barrier, preventing head lice medication from reaching the scalp. [18] X Trustworthy Source Centers for Disease Control and Prevention Main public health institute for the US, run by the Dept. of Health and Human Services Go to source Read the instructions carefully. Otherwise, the treatment might be ineffective. Make sure you apply a second treatment and wait the appropriate time. If you retreat too soon after the first treatment, you may not remove all the lice. [19] X Trustworthy Source Centers for Disease Control and Prevention Main public health institute for the US, run by the Dept. of Health and Human Services Go to source Reinfestation is also common. Make sure you avoid people who are currently infested with head lice and treat your home to remove any lice that have wandered from your scalp. [20] X Trustworthy Source Centers for Disease Control and Prevention Main public health institute for the US, run by the Dept. of Health and Human Services Go to source