Why is head lice itchy

Go through small sections of hair at a time. Wetting the hair temporarily stops the lice from moving, and the conditioner makes it easier to get a comb through the hair. When possible, it works best to have someone else do the combing and removal. You may have heard that petroleum jelly, mayonnaise, or olive oil can suffocate head lice, but these treatments may not be effective.

If you choose to get rid of lice without using medicine, you'll need to remove lice and nits carefully each week, for at least 3 weeks in a row. Watch for any live lice and take action if you see them. Scratching a lot can lead to a scalp infection.

Call your doctor as soon as possible if:. A few important things to NOT do: Don't use a hairdryer after applying scalp treatments. Some treatments for lice use flammable ingredients and can catch on fire.

Don't use pesticide sprays or hire a pest control company to try to get rid of the lice; these can be harmful. Don't use essential oils such as ylang ylang oil or tea tree oil to treat lice on the scalp. They can cause allergic skin reactions and aren't approved by the U. Don't ever use highly flammable chemicals such as gasoline or kerosene.

Lice can be tricky to get rid of because nits can remain unhatched on your head or you might pick up lice that are still on bedding or other items. Here's what to do if you've had lice — or someone in your family has:. Reviewed by: Michelle P. Tellado, MD. Larger text size Large text size Regular text size. What Are Head Lice? It's best to treat head lice right away to prevent them from spreading. How Are Head Lice Treated? The two main ways to treat lice are: medicine removing by hand Medicine.

A single application is enough for most patients, but it should be reapplied in 7 to 9 days if live lice are still seen. It is suitable for children aged 6 years or older.

Malathion is flammable and may cause chemical burns. Leave the hair to dry naturally after applying it, and do not use a hair dryer, curling iron, or flat iron while the hair is wet. Benzyl alcohol lotion 5 percent is a prescription-only drug that is applied topically and left on for 10 minutes.

It does not kill eggs, so it must be repeated after 9 to 10 days. It is only suitable for infants and children over the age of 6 months. This is a prescription drug that is applied to dry hair and rinsed off after 10 minutes. Made from a naturally occurring soil bacterium, it causes lice to become paralyzed and then die. It also contains benzyl alcohol. Spinosad is safe and effective for the treatment of head lice, and most people will have no lice after a single treatment.

It is not necessary to use a nit comb after treatment. Spinosad topical suspension is approved for use in children aged 6 months and older, but its safety has not been established in children younger than 4 years. Ivermectin lotion 0. Topical ivermectin 0. This is a one-time-use, topical treatment that is suitable for children aged 6 months and older. Any leftover medicine must be thrown out, not reused. Ivermectin can be fatal to some breeds of dog and should be kept away from household pets.

Here are some steps for using head-lice products safely. If head lice are found on one family member, all household members should be checked , and those with live lice or nits within one half-inch of the scalp should be treated.

When an infestation is found in a healthy child, it usually involves fewer than 20 mature lice. Head lice are visible with the naked eye, but they can be difficult to see, even on close inspection. Nits can easily be confused with dandruff , hair spray droplets, or dirt particles. As a result, misdiagnosis is common. Nits can remain glued to hair long after the live lice have been removed. Unhatched eggs and empty shells may remain after a live infestation is successfully treated.

A magnifying lens may help locate crawling lice and identify a developing nymph inside a viable egg. A diagnosis can be confirmed if a live louse is found crawling on the head, but this can be difficult because lice avoid light and they can crawl quickly. A fine-toothed louse comb may help identify live lice. The comb works better on wet hair, but can also be used on dry hair to trap even small lice.

After each comb-through, wipe the comb on a wet paper towel. Examine the scalp, comb, and paper towel carefully. The following measures can help reduce the risk of finding head lice in the home:. A head lice infestation results from the direct transfer of lice from the hair of one person to the hair of another through head-to-head contact. To survive, an adult head louse must feed on blood. If they fall off, they will die within 1 to 2 days. Head lice cannot fly or jump, but sometimes they can be transmitted on personal items, so it is sensible to avoid sharing brushes, combs, headbands, headphones, towels, clothing, or hats with anyone who has an active infestation.

An infestation does not result from dirty hair or poor hygiene, and it can occur in hair of any length or condition. Head lice cannot be passed on to or caught from animals. Head lice may be able to survive under water for several hours, and chlorine levels in a swimming pool do not kill them. However, they are unlikely to be spread through pool water. They tend to hold tightly to hair when submerged in water.

African American people get head lice less commonly than other people. This may be because the shape of coily hair makes it hard for the lice to grip…. Pubic lice are insects that live in coarse body hair and feed on blood.

Various treatments are available, which it is essential to use correctly. Research into whether home remedies can eliminate lice is ongoing. It is possible for nits to remain present several days after they have hatched and months after successful treatment.

After the hair is brushed to remove tangles, a fine-toothed comb with teeth 0. After each stroke, the comb should be inspected for live lice. The entire head should be combed systematically twice. It usually takes about 1 minute to find the first louse. Treatment is recommended for those with a clear diagnosis with living lice. When infestation has been determined, all members of the household and close contacts should be inspected.

It is also important to treat any family members who share the same bed with the infected individual, even if no live lice are found. Pharmacologic treatment options are classified as either pediculicidal killing nymphs and adult lice only , ovicidal killing nits, but not affect-ing nymphs or adult lice , or both.

The available OTC pediculicides in the U. Both agents are neurotoxic to lice, causing paralysis and death, but have extremely low mammalian toxicity. Permethrin: Permethrin has been the most studied agent and is the least toxic to humans.

No major adverse effects have been reported with its use. Minor adverse effects include rash, pruritus, pain, burning, and tingling. Compared to pyrethrins, permethrin is less allergenic and does not cause allergic reactions in individuals with plant allergies. The product is left on for 10 minutes then rinsed off. Treatment should be followed by combing the hair with a fine-toothed comb. Permethrin leaves a residue on the hair shaft that allows it to maintain activity for up to 10 days after treatment.

Pyrethrins Plus Piperonyl Butoxide: Pyrethrins are derived from chrysanthemum flowers; therefore, patients who are allergic to these plants or ragweed should avoid their use. When compared to permethrin, these products demonstrated less pediculicidal efficacy. This product is available as a shampoo and mousse. It should be applied to dry hair and left on for 10 minutes before rinsing and combing hair with a fine-toothed comb.

A retreatment in 9 days, optimally, is needed to kill newly emerged nymphs from eggs that survived. The adverse effect profile is similar to permethrin and is generally well tolerated. The issue of head lice resistance has recently been in the spotlight. In August , a press conference was held to discuss the findings of an analysis of lice samples collected from across the U. The findings indicated that lice in at least 25 states have developed resistance to pyrethroids.

Various other products have been used in the eradication of lice, including essential oils and occlusive agents such as petrolatum shampoos, margarine, mayonnaise, butter, and olive oil. The use of essential oils, such as tea tree and lavender oil, is not recommended, as much of the evidence available is unclear. These oils are also a source of contact irritation, leading to inflammation and allergic contact dermatitis.

Only items that have been used by the affected individual within the last 24 to 48 hours before treatment should be considered for cleaning. Items include clothing, headgear, bedding, furniture, and carpeting.

Combs and brushes can be soaked in hot water for 10 minutes. Furniture, carpets, car seats, and other fabrics should be vacuumed thoroughly and routinely. Keep in mind, however, that the risk of infestation from lice that have fallen from a host is very rare, and viable nits are unlikely to incubate and hatch at room temperatures. These individuals need to be counseled on the appropriate selection and proper use of available OTC products.

Many patients fail to reapply the treatment after 7 to 10 days as instructed, leading to treatment failure. If after two to three treatment applications lice are still present, patients should be referred to their healthcare provider. In addition, patients need to be educated regarding strategies to prevent future infestations. Pharmacists can help ease the social stigma related to this condition by dispelling the common myths associated with head lice.

People get head lice from someone who already has them; usually the transmission is by direct head-to-head contact. It is because of this close contact that large outbreaks of lice infestation are common in places such as day care centers and schools.

Head lice may also be spread by sharing items like hats and combs, but this is rare. Itching is traditionally the first complaint.