Lice are parasitic insects that can live on people's heads and bodies. They survive by feeding on human blood. Over-the-counter and prescription medicines are available for treatment.

Lice Overview

Reviewed: May 22, 2014

Lice are tiny, wingless, parasitic insects that feed on human blood. Lice are easily spread through close personal contact and by sharing belongings. Dogs, cats, and other pets do not spread human lice. Lice move by crawling. They cannot hop or fly.

Several types of lice exist.

  • Head lice. These lice live on your scalp. They are easiest to see at the nape of your neck and over your ears.
  • Body lice. These lice live in clothing and on bedding and move onto your skin to feed. Body lice most often affect people who are not able to bathe or launder clothing regularly, such as homeless or transient individuals.
  • Pubic lice. Commonly called crabs, these lice occur on the skin and hair of your pubic area and, less frequently, on coarse body hair, such as chest hair, eyebrows or eyelashes.

People with good personal hygiene habits can still get lice. Unless treated properly, this condition can become a recurring problem.

Both over-the-counter and prescription medicines are available for treating lice.

Lice Symptoms

Symptoms of lice may include:

  • intense itching
  • tickling feeling from movement of hair.
  • rash
  • visible nits (lice eggs) or crawling lice

Lice Causes

You get lice by coming into contact with either lice or their eggs. Eggs hatch in about 1 week. Lice cannot fly or walk on the ground. They spread through several modes of contact.

  • Head-to-head or body-to-body contact. This may occur as children or family members play or interact closely.
  • Proximity of stored belongings. Storing infested clothing in closets, in lockers or on side-by-side hooks at school, or storing personal items such as pillows, blankets, combs and stuffed toys in proximity at home can permit lice to spread.
  • Items shared among friends or family members. These may include clothing, headphones, brushes, combs, hair decorations, towels, blankets, pillows and stuffed toys.
  • Contact with contaminated furniture. Lying on a bed or sitting in overstuffed, cloth-covered furniture recently used by someone with lice can spread them. Lice can live for one to two days off the body.
  • Sexual contact. Pubic lice usually spread through sexual contact and most commonly affect adults.

Lice Diagnosis

Lice are diagnosed by visual inspection of the body or your belongings.

Head live are diagnosed after a live young or adult louse in the hair or on the scalp is found, or after 1 or more nits is seen on hair shafts located within 1/4 inch of the scalp. If you do not see any live lice or you see nits that are more than 1/4 inch away from the scalp, the infestation is probably no longer active. Nits should be removed to prevent a recurrence.

Body lice are diagnosed if eggs or crawling lice are found in the seams of clothing or on bedding. It is possible to see a body louse on skin if it crawls there to feed.

Pubic lice are diagnosed when moving lice or nits are seen on hair in the pubic area or on other areas of coarse hair, such as chest hair, eyebrows or eyelashes.

Living With Lice

You can get rid of lice with by cleaning yourself or your child and any personal belongings that may be contaminated.

The following steps may help you eliminate lice infestations.

  • Use lotions and shampoos. Several over-the-counter lotions and shampoos are designed to kill lice.
  • Comb wet hair. Use a fine-toothed or nit comb to physically remove the lice from wet hair. This method may be used in combination with other treatments and is usually recommended as the first line treatment for children under the age of 2 years.
  • Wash contaminated items. Wash bedding, stuffed animals, clothing, and hats with hot, soapy water and dry them at high heat for at least 20 minutes.
  • Seal unwashable items. Place items that cannot be washed in an airtight bag for 2 weeks.
  • Vacuum. Vaccum the floor and furniture thoroughly.
  • Cover furniture. Use a plastic painter's dropcloth to cover furniture for 2 weeks to prevent acquiring another case of lice.
  • Wash combs and brushes. Use very hot, soapy water to wash combs and brushes, or soak them in rubbing alcohol for an hour.

Most lice treatment involves self-care steps you can take at home. In most cases, killing lice on your body is not difficult, but getting rid of all the nits and avoiding contact with other lice at home or school can be challenging.

Lice Treatments

Use medications that treat lice only as directed. Applying too much can cause red, irritated skin.

Treatment for head lice may involve:

  • Over-the-counter products. Shampoos containing pyrethrin (Rid, others) or permethrin (Nix) are usually the first option used to combat lice infestations. These work best if you follow the directions very closely. If over-the-counter preparations do not work, your doctor can prescribe shampoos or lotions that contain different ingredients.
  • Prescription medications. Malathion (Ovide) is a prescription medication that you apply to your hair and then rub into your hair and scalp. Malathion is flammable, so keep it away from heat sources such as hair dryers, electric curlers and cigarettes. Benzyl alcohol lotion (Ulesfia) is a prescription treatment that you apply to the scalp and hair for 10 minutes and then rinse off with water. The treatment is repeated 7 days later. Ivermectin lotion (Sklice) is a topical, single-dose treatment for head lice. Apply the lotion directly to dry hair and the scalp for 10 minutes and then rinse with water. Do not repeat this treatment without talking to your doctor first. Spinosad topical suspension (Natroba) is a newer prescription treatment for head lice. Apply the medication to dry hair and the scalp for 10 minutes and then rinse with water. Repeat the treatment after 7 days only if live lice are still present. Finally, lindane is a prescription shampoo that is sometimes prescribed when other measures fail. Lindane is no longer recommended as a first line treatment for head lice.

Body lice usually do not require medications as part of treatment. However, you must take the same self-care measures, such as treating clothing and other items, as you would for head lice. If self-care measures fail to get rid of the lice, your doctor might recommend trying one of the nonprescription or prescription treatments for head lice.

Pubic lice can be treated with many of the same nonprescription and prescription treatments used for head lice. Follow the package instructions carefully. Talk to your doctor about treatment of lice and nits on eyebrows or eyelashes.

Lice Other Treatments

Lice Prognosis