Diagnosis

During an examination, your doctor may examine you for lice using a magnifying lens and check for nits using a special light, called a Wood's light, which makes the nits look pale blue.

Head lice

A diagnosis of head lice can be made after a live young or adult louse in the hair or on the scalp is found, or after one or more nits is seen on hair shafts located within 1/4 inch (6.4 millimeters) of the scalp.

If you don't see any live lice or you see nits that are more than 1/4 inch away from the scalp, the infestation is probably no longer active.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

A diagnosis of body lice may be made if eggs or crawling lice are found in the seams of clothing or on bedding. It's possible to see a body louse on skin if it crawls there to feed.

Pubic lice

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.

Treatment

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

Head lice

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. In some geographical locations, lice have grown resistant to the ingredients in over-the-counter lice treatments. If over-the-counter preparations don't 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. If you're pregnant or breast-feeding, talk to your doctor before using this product.

    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. Seven days later you repeat the treatment. Possible side effects include irritation of the skin, scalp and eyes as well as numbness at the application site. This medication isn't recommended for children younger than 6 months of age.

    Ivermectin lotion (Sklice) is a topical, single-dose treatment for head lice. You 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. Possible side effects include eye irritation or redness, dandruff, dry skin, and a burning sensation at the application site. This medication isn't recommended for children younger than 6 months of age.

    Spinosad topical suspension (Natroba) is a newer prescription treatment for head lice. You apply the medication to dry hair and the scalp for 10 minutes and then rinse with water. Repeat the treatment after seven days only if live lice are still present. Possible side effects include redness or irritation of the eyes and skin. This medication isn't recommended for children younger than age 4.

    Finally, lindane is a prescription shampoo that's sometimes prescribed when other measures fail. However, due to increasing resistance of lice to this medication and to serious neurological side effects, lindane is no longer recommended as a first line treatment for head lice.

Body lice

If you have body lice, you don't need 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

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

Self-care important

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.

Lifestyle and home remedies

You can get rid of lice with a patient, thorough approach that involves cleaning yourself or your child and any personal belongings that may be contaminated.

These steps may help you eliminate lice infestations:

  • Use lotions and shampoos. Choose from among several over-the-counter lotions and shampoos (Nix, Rid, others) designed to kill lice. Apply the product according to package instructions. You may need to repeat treatment with the lotion or shampoo in seven to 10 days. These lotions and shampoos typically aren't recommended for children under age 2.
  • Comb wet hair. Use a fine-toothed or nit comb to physically remove the lice from wet hair. Repeat every three to four days for at least two weeks. This method may be used in combination with other treatments and is usually recommended as the first line treatment for children under age 2.
  • After shampoo treatment, rinse your hair with vinegar. Grasp a lock of hair with a cloth saturated with vinegar and strip the lock downward to remove nits. Repeat until you've treated all the hair in this way. Or soak hair with vinegar and leave it on for a few minutes before combing. Then towel-dry the hair. These methods can help remove nits from the hair shaft.
  • Wash contaminated items. Wash bedding, stuffed animals, clothing and hats with hot, soapy water — at least 130 F (54 C) — and dry them at high heat for at least 20 minutes.
  • Seal unwashable items. Place them in an airtight bag for two weeks.
  • Vacuum. Give the floor and furniture a good vacuuming.
  • Cover furniture. Use a plastic painter's dropcloth to cover furniture for two weeks to prevent acquiring another case of lice. Don't do this if you have a toddler who may become tangled in a plastic sheet and suffocate.
  • Wash combs and brushes. Use very hot, soapy water — at least 130 F (54 C) — or soak combs and brushes in rubbing alcohol for an hour.

Preparing for your appointment

Often, you can get rid of lice with over-the-counter treatments and by properly washing contaminated household items, such as sheets, towels and clothes. If these measures don't work, see your primary care medical provider.

Here's some information to help you get ready for your appointment, and know what to expect from your doctor.

What you can do

  • Write down any symptoms you're experiencing, including any that may seem unrelated to the reason for which you scheduled the appointment.
  • Write down key personal information, including when you might have been exposed to lice, whom you might have exposed and what household items might be contaminated.
  • Make a list of all medications, vitamins or supplements that you're taking.
  • Ask a family member or friend along, if possible. Sometimes it can be difficult to soak up all the information provided during an appointment. Someone who accompanies you may remember something that you missed or forgot.
  • Write down questions to ask your doctor. Your time with your doctor is limited, so preparing a list of questions ahead of time will help you make the most of your time together. List your questions from most important to least important in case time runs out.

Some basic questions to ask your doctor include:

  • How do I treat lice?
  • Is there a generic alternative to the medicine you're prescribing?
  • How do I rid my household items of lice?
  • Who do I need to inform about my condition?
  • What other measures do I need to take to avoid re-infesting myself or others?
  • Is my condition likely temporary or chronic?
  • Are there any brochures or other printed material that I can take home with me? What websites do you recommend?
  • Should I plan for a follow-up visit?

In addition to the questions that you've prepared to ask your doctor, don't hesitate to ask questions during your appointment when you don't understand something.

What to expect from your doctor

Your doctor is likely to ask you a number of questions, such as:

  • When did you first begin experiencing symptoms?
  • How were you exposed to lice?
  • Is there anyone you might have exposed to lice?
  • How severe are your symptoms?

What you can do in the meantime

If you think or know you have lice, avoid sharing personal items, bedding, towels or clothing. Bathe and follow self-care measures, including washing contaminated items in hot water.

If you think or know you have a pubic lice infestation, also avoid sexual activity until you've been treated.

March 28, 2015
References
  1. Head lice: Frequently asked questions. Centers for Disease Control and Prevention. http://www.cdc.gov/parasites/lice/head/gen_info/faqs.html. Accessed March 9, 2015.
  2. Body lice: Frequently asked questions. Centers for Disease Control and Prevention. http://www.cdc.gov/parasites/lice/body/gen_info/faqs.html. Accessed March 10, 2015.
  3. Pubic "crab" lice: Frequently asked questions. Centers for Disease Control and Prevention. http://www.cdc.gov/parasites/lice/pubic/gen_info/faqs.html. Accessed March 10, 2015.
  4. Goldstein AO, et al. Pediculosis capitis. http://www.uptodate.com/home. Accessed March 10, 2015.
  5. Goldstein AO, et al. Pediculosis pubis and pediculosis ciliaris. http://www.uptodate.com/home. Accessed March 10, 2015.
  6. Head lice: Treatment. Centers for Disease Control and Prevention. http://www.cdc.gov/parasites/lice/head/treatment.html. Accessed March 10, 2015.
  7. Body lice: Treatment. Centers for Disease Control and Prevention. http://www.cdc.gov/parasites/lice/body/treatment.html. Accessed March 10, 2015.
  8. Pubic "crab" lice: Treatment. Centers for Disease Control and Prevention. http://www.cdc.gov/parasites/lice/pubic/treatment.html. Accessed March 10, 2015.
  9. Hoecker JL (expert opinion). Mayo Clinic, Rochester, Minn. March 12, 2015.