Head lice are insects with six claws and no wings that cannot hop or fly. Lice move by crawling; their claws hold tightly onto hair. They’re gray-white or tan and the size of sesame seeds, and they feed on human blood four or five times a day. Lice live and breed within a quarter inch of the hair from the base of the scalp, especially near the ears and neck. Head lice may also thrive in eyebrows and beards. Lice are most active at night.
Head lice are very contagious, and they spread by direct contact with someone who is infested or by sharing clothing (like hats) with someone who has lice. Female lice attach their eggs firmly to hair. Lice eggs are called nits, which are usually yellow to white — these are extremely small and can be confused with dandruff. Nits hatch in eight or nine days, and they reach adult size nine to 12 days after hatching. Lice live up to 30 days. Females can lay 50 to 150 eggs in their lifetime. If lice fall off the scalp, they die within two days.
Six to 12 million children, mostly between 3 and 12 years of age, get lice each year. It’s more common in girls and in individuals living in crowded conditions. Head lice is less common in African-Americans.
[Read: How to Get Rid of Lice .]
How Can I Tell if My Child Has Head Lice?
| Table 1: Detecting Lice |
|---|
| Follow these three steps: |
| 1. Wet the hair to make it easier to see lice and prevent them from moving quickly. |
| 2. Use a bright light and a magnifying glass when checking for lice. |
| 3. Separate sections of hair. Slowly comb each section with a lice comb. Pay close attention to the hair behind the ears and near the neck. Because nits cannot move, they are more likely to be seen. |
| If you don’t see lice or nits, the symptoms are due to other causes. |
| Source: Pharmacy Times |
The first symptom of head lice is intense itching. Other symptoms include a tickling sensation or a feeling that something is moving in the hair. Small red bumps on the scalp or neck may also be present (Table 1). Constant scratching can result in open wounds and infections.
Myths and Facts
Myth: Pets spread head lice.
Fact: Lice cannot live on pet fur.
Myth: Head lice carry diseases.
Fact: Lice do not carry other diseases.
Myth: Head lice thrive in dirty households.
Fact: The cleanliness of a person or house has no role in spreading head lice.
Myth: Insect sprays kill lice.
Fact: Insect sprays should never be used. They may contain harmful chemicals.
Myth: Swimming spreads lice.
Fact: Lice tightly hold onto hair when underwater. Chlorine in pool water cannot kill lice.
[See: Pharmacists’ Top Recommended Dandruff Shampoos.]
| Table 2: Treating Head Lice With Products Containing Pyrethrins |
|---|
| Carefully read and follow the directions |
| Use only one product. Using more can be harmful. Use the comb that comes with the shampoo. |
| Examine hair eight to 12 hours after treatment. If you see moving lice, the product may not be working. Do not treat again. Call your doctor. |
| Wait two days before washing hair. Comb hair for lice at least once a day. |
| Repeat the treatment as recommended on the package. A second treatment is usually done seven to nine days after the first treatment. Lice shampoos are more successful at killing adult lice than nits. A second treatment can kill lice that hatch after the first treatment. |
| After applying the second treatment, wait two days before washing hair. Continue to comb the hair daily for two weeks. |
| Call your doctor if your find lice in eyebrows. |
| Source: Pharmacy Times |
Head lice are treated with OTC products containing pyrethrins. Rid and Nix are brand names of products containing pyrethrins (Table 2). Common side effects of pyrethrins are skin irritation and the feeling that the scalp is burning and itchy. People allergic to ragweed or chrysanthemums should avoid pyrethrins.
Two treatments spaced seven to nine days apart usually get rid of lice. The second treatment is needed to kill nits that have hatched after the first treatment. Because products may not kill all the nits, you should continue to comb for nits for at least two weeks following the second treatment. Some lice are resistant to treatment. Your doctor can prescribe a cream, lotion or shampoo that kills resistant lice. There is some evidence that tea tree oil and lavender oil are effective against lice. While the American Medical Association recommends tea tree oil, the National Institutes of Health does not recommend herbal treatments.
If you want to avoid medications, the following methods are recommended for treating head lice.
Apply an oil (like cooking oil) or petroleum jelly to wet hair. Using a lice comb, remove nits and lice. Comb the hair for 30 minutes every two or three days for a two-week period.
Remove all hair by shaving the entire head and neck. Lice die if they cannot attach to hair.
[See: Pharmacists’ Top Recommended Lice Treatments.]
Prevention
| Table 3: Preventing Head Lice |
|---|
| Avoid head-to-head contact with other individuals. |
| Do not share clothing, combs or hairbrushes with other individuals. |
| Bring your own pillow and towel when sleeping at another person’s house. |
| Do not lie on beds, couches, pillows and carpets that have recently been in contact with an infested person. |
| Never hang coats and hats from more than one individual on top of one another. |
| Wash clothing in hot water, and dry it on the highest heat cycle on your dryer. Nonwashable items should be placed in sealed plastic bags for two weeks. |
| Vacuum frequently, including furniture, stuffed animals and car seats. |
| If a person has head lice, others in the same household need to be observed for head lice. Use treatments only if lice are detected. |
| Report head lice to your child’s school. Some schools have a “no lice” policy. |
| Source: Pharmacy Times |
Teach your children about head lice and ways to prevent it (Table 3).
Note: This article was originally published on Aug. 4, 2014 on PharmacyTimes.com. It has been edited and republished by U.S. News. The original version, with references, can be seen here.
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Ways to Treat Head Lice originally appeared on usnews.com
