Make sure you have enough treatment product. If the person being treated for head lice has very long hair, meaning it falls past their shoulders, you may need two bottles of medicated shampoo or lotion to complete the treatment. (3)Change clothes. Any person receiving treatment for head lice should remove clothing that can become wet or stained during the process. (3)Wash hair this way. Some treatments call for washing the infested person’s hair prior to treatment. But conditioners and silicone-based additives in shampoos may impair the treatment’s ability to adhere to the hair. Look for shampoos that are silicone-free. (1)Check with the pediatrician. If the infested person is a child who is 2 years old or younger, call the child’s doctor before using any medicine. (4)Consult your doctor. It’s advised that pregnant or breastfeeding women refrain from using or applying lice medicine without first checking with a physician. (4)Wear gloves. Protect hands when applying lice medicine to the scalp. (5)Treat others. It’s prudent to also check and treat members of the household who have shared pillows or beds, or had other head-to-head time with the person with the active infestation. (3)

Permethrin (Nix, Elimite) Permethrin is the most studied lice treatment in the United States, and the least toxic medicinal option. It should be applied to hair that’s been freshly shampooed with a nonconditioning product and toweled dry. After 10 minutes, rinse. This treatment kills lice, but not lice eggs, so should be repeated nine days after the first treatment for optimal results. (1) This is approved for children ages 2 months and older. (4)Pyrethrins and piperonyl butoxide (RID, Pronto, or Triple X) Because pyrethrins and piperonyl butoxide treatment (available in shampoo or mousse) is derived from the chrysanthemum, those with related allergies should avoid it. This treatment is applied to dry hair and left on for 10 minutes before rinsing it out. Again, lice are killed — but not the lice eggs — so it’s best to treat again after nine days. (1) This is appropriate to use on children who are at least 2 years old. (4)

Benzyl alcohol lotion (Ulesfia) Unlike other medication, benzyl alcohol lotion does not poison the lice, but kills them by asphyxiation. It should be applied to dry hair and left on for 10 minutes before rinsing it out. Repeat after nine days. This treatment is approved for use in children older than 6 months. (4)Malathion (Ovide) While very effective at killing both lice and lice eggs, malathion is not considered a first-line treatment because it needs to remain on hair for 8 to 12 hours to work. But a single application is often adequate for most patients. If lice are still seen after seven to nine days, the treatment should be reapplied. Malathion has been approved for use on children 6 years and older. (4)Spinosad (Natroba) Spinosad is another medication that kills both lice and lice nits. It should be applied to dry hair and left on for 10 minutes before rinsing it out, and repeated after seven days if live lice are spotted. Spinosad is approved for use on children 6 months and older. (4)Ivermectin (Stromectol, Sklice) This treatment is also applied to dry hair and rinsed out after 10 minutes. While ivermectin only kills lice — not lice eggs — when the treated lice eggs hatch, the newly born lice are unable to properly feed and therefore die. Only one application is required. Treatment is approved for children 6 months and older. (4)Lindane shampoo While lindane shampoo is approved by the Food and Drug Administration (FDA) for the treatment of head lice, it is not a first–line treatment. Instead, its use should be restricted to those who have not had success with — or cannot tolerate — other treatments. (3) It can be toxic, especially for those with a seizure disorder and for pregnant or breastfeeding women.Ivermectin Oral When other topical treatments fail, oral ivermectin may be an option. While it effectively treats a head lice infestation with two doses eight days apart, side effects may include nausea and vomiting. (Children must weigh at least 33 pounds to take this medication.) (2)

Never cover the hair with a plastic bag. Do not place a plastic bag or a shower cap over a person’s head in order to suffocate lice. (5)Avoid the shower. Use warm — not hot — water to rinse the lice treatment medicine off over a sink. Never do this during a shower or bath. (4)Change clothes. Have the newly treated individual change into clean clothing after treatment. (3)Avoid shampoo and conditioner. It’s recommended that you refrain from rewashing treated hair for one to two days post-treatment. (3) And skip the conditioner for 10 days afterward. (5)Look for topical reactions. After treatment, some people may experience itching or mild burning on their scalp, which can last for days. If this occurs, a physician may prescribe topical corticosteroids and oral antihistamines to quell the symptoms. (1)Refrain from a too-soon retreatment. If a few live lice are still moving, but more slowly, 8 to 12 hours post-treatment, simply wait. Sometimes the treatment takes a bit longer to eradicate live lice. (3)

For everyone else, additional nit-picking is likely needed, too. The reason: Nits cannot be washed or brushed out of the hair, and no medication (prescription or OTC) can guarantee that 100 percent of the lice eggs will be killed, especially the ones within 1 centimeter of the scalp. (1) If all lice nits are not removed, they’ll likely hatch, and hair will become reinfested. To make this tedious process easier, wet the person’s hair and then part it into small sections using hair clips. Then use a magnifying glass to better see lice and lice eggs, and a fine-toothed metal lice comb to go through the hair. (You may want to use white vinegar on the wet hair as well. It’s thought that this may help loosen the “glue” that holds the nits tightly to the hair.) (5) After each comb-through, be sure to wipe the nit comb on a wet paper towel. (4) The whole process can take more than an hour, depending on hair length and how many lice eggs are involved. (5) Do this every two to three days after treatment for two to three weeks. (3)

Supplemental Measures to Help Stave Off a Reinfestation

In addition to treating the actual person with the head lice infestation, consider treating the environment, too. While head lice cannot survive for long when not attached to a human host, it’s still considered shrewd to take the following steps:

Do the laundry. Change and launder (in hot water) the infested person’s pillow cases, bedding, pajamas, towels, and other items that may have come in contact with the infested person’s head within 24 to 48 hours of diagnosis. Dry everything on the hot cycle for at least 20 minutes. (1)Soak brushes. Submerge combs, brushes, barrettes, and hair bands in hot water for 10 minutes. (1)Vacuum up. Use a vacuum on the carpets, furniture, car seats, beds, and other items that have been in contact with the head of the person with infestation within the past day or two. (1)Seal other items. Although not usually necessary, consider placing pillows and stuffed toys in a tightly sealed plastic bag for two weeks to suffocate any remaining lice nits or lice. (1)

Misuse of treatment When lice treatment is reapplied too soon — or too late — this can cause a continuous infestation. That’s why it’s imperative to carefully follow treatment instructions. (6)Misdiagnosis of lice “There are a lot of misdiagnoses of head lice,” says Dr. Pollack. In fact, his study published in The Pediatric Infectious Disease Journal concluded that most of the presumed “lice eggs” and “lice” that doctors, nurses, and others have submitted to labs for identification were ultimately found not to be lice. (7)Reinfestation Even if a person is successfully treated for head lice, they may become infested once again from another infested person. (6)

The American Academy of Pediatrics notes that unless lice resistance has been seen in your community, your first choice of treatment for all confirmed cases of head lice (meaning live, active lice) should still be OTC medication containing permethrin or pyrethrins. Even though some over-the-counter treatments may be less effective than they were previously, these are still the treatments that work best the majority of the time. (1)

Essential oils Even though essential oils, like ylang-ylang, tea tree, and lavender oil, are widely used, they’re natural products, which means they’re not required to meet FDA efficacy and safety standards. Because of this, the use of these types of herbal products should be avoided in infants and children, concluded a report published in May 2015 in the journal Pediatrics. (1)Suffocating agents, like Cetaphil, mayonnaise, and olive oil These are all considered occlusive agents, which means they’re supposed to work by suffocating lice. There’s mostly anecdotal evidence to support the effectiveness of suffocating agents. In addition, an uncontrolled, nonrandomized study published in the journal Pediatrics reported a 96 percent “cure” rate when Cetaphil cleanser was applied to hair, dried on with a blow-dryer, left overnight, and rinsed in the morning. (Repeat once a week for three weeks.) (8)Dimethicone lotion This lice treatment hair rinse works by dissolving the waxy exoskeleton of the louse, leading to dehydration and death. (1) A study published in June 2015 in the journal BMC Pediatrics found that 98 percent of children were free of live lice, and 55 percent were free of viable lice eggs, after one treatment of 100 percent dimethicone. (9)The AirAllé This is special machine found at professional lice treatment centers that uses a 30-minute blast of hot air to kill lice. At least one study has shown that this can be an effective method, knocking out nearly all lice eggs and 80 percent of live lice after one treatment (10) (A regular blow-dryer does not work in the same way and should not be used as treatment, since blow-dryers can cause lice to become airborne.) (1) How to Treat and Prevent Lice - 68