Lice – causes, symptoms, treatment, prevention

Lice are tiny, wingless, parasitic insects that feed on your blood. Lice are easily spread — especially by schoolchildren — through close personal contact and by sharing belongings.

Several types of lice exist:

  • Head lice. These lice develop on your scalp. They’re easiest to see at the nape of your neck and over your ears.
  • Body lice. These lice spend most of their time in the seams and folds of your clothing.
  • Pubic lice. Commonly called crabs, these lice occur on the skin and hair of your pubic area and on eyelashes.

You or your child can have good personal hygiene habits and still get lice. Unless treated properly, this condition can become a recurring problem.

You can get lice by coming into contact with either lice or their eggs. Eggs hatch in about one week. Lice can’t fly or walk on the ground. They spread by:

  • Head-to-head or body-to-body contact. This may occur as children or family members play or interact closely.
  • Close proximity of stored belongings. Storing infected clothing in closets, lockers or on side-by-side hooks at school, or storing personal items such as pillows, blankets, combs and stuffed toys in close proximity at home can permit lice to spread.
  • Sharing items. These may include clothing, headphones, brushes, combs, hair decorations, towels, blankets, pillows and stuffed toys.
  • Contact with contaminated furniture. Lying on a bed, sitting in furniture or even using a toilet seat recently used by someone infected with lice can spread them. Head lice live for up to two days off the body.
  • Sexual contact. All three forms of lice can spread in this manner.

Signs and symptoms of lice include:

  • Intense itching.
  • Lice on the scalp, the body, clothing, or pubic or other body hair. Lice can be 0.08 to 0.16 inches (2 to 4 millimeters) in size.
  • Lice eggs (nits) on hair shafts. Nits resemble tiny pussy willow buds. Nits can be mistaken for dandruff, but unlike dandruff, they can’t be easily brushed out of hair.
  • Small, red bumps on the scalp, neck and shoulders.


Head lice
Over-the-counter lotions or shampoos (Nix, Rid, others) are usually the first line of defense against head lice. However, if nonprescription products don’t kill the lice, your doctor can prescribe a stronger shampoo or lotion.

  • Malathion (Ovide). This has been re-approved as a prescription drug for treating head lice. Malathion is flammable, so keep it away from heat sources such as hair dryers, electric curlers and cigarettes. If you’re pregnant or breast-feeding, talk to your doctor before using this product.
  • Lindane. Another type of prescription treatment for lice contains the medication lindane. Your doctor may not recommend lindane if you weigh less than 110 pounds, have used it in the past few months or if you’re a women who is breast-feeding. Side effects may include skin irritation, seizures and, rarely, death. Using lindane in higher than recommended amounts, or for longer than recommended, increases the risk of side effects.

Use these medications only as directed. Applying too much can cause red, irritated skin.

Self-care important, too
Whether you use over-the-counter or prescription shampoo to kill lice, much of the treatment involves self-care steps you can take at home. These include making sure all the nits are removed and that all clothing, bedding, personal items and furniture are decontaminated. In most cases, killing lice on your body isn’t difficult. The challenge is getting rid of all the nits and avoiding contact with other lice at home or school.

Body lice
If you have body lice, you don’t need treatment, yourself. However, you must take the same self-care measures, such as treating clothing and other items, as you would for head lice.

Pubic lice
Pubic lice can be treated with the same nonprescription and prescription treatments used for head lice.


It’s difficult to prevent the spread of head lice among children in child care and school settings. There’s so much close contact among children and their belongings that lice can spread easily. It’s no reflection on your hygiene habits or those of your children, and it’s not a failure on your part as a parent if your child gets head lice. The best approach is simply to take thorough steps to get rid of the lice — and their eggs — so that you don’t have more lice to deal with.

Ask your child not to share personal belongings such as:

  • Hats
  • Scarves
  • Coats
  • Combs
  • Brushes
  • Hair decorations
  • Headphones

However, it’s not realistic to expect that you and your child can eliminate all the types of contact that may result in the spread of lice.

Your child may have nits in his or her hair but not necessarily develop a case of head lice. Some nits are empty eggs. However, nits that are found within 1/4 inch of the scalp should be treated — even if you find only one — to prevent the possibility of hatching. Nits that are farther away from the scalp are probably from an old infestation and don’t need to be treated.