HEAD LICE

Head lice, or pediculosis capitis, is a common problem in children and adults of all socio-economic classes and races. It is caused by a wingless insect that lives on only humans. The female deposits eggs or nits on human hair about one-half inch from the scalp. The eggs are cemented to the hair shaft and hatch after 8-10 days. Head lice survive up to 3 days away from the human host and nits can survive up to 10 days so that lice can be transferred from one person to another through contact with headgear, hats, brushes, combs, bedding, rugs, etc.

There are several treatment options:

Over-the-counter agents are readily available. We prefer permethrin or Nix used according to directions provided with the following advise:

During all stages of treatment it is important to use only shampoos that contain no conditioning agents. Do not use cream rinses. These can coat hairs and protect the lice from the medication.

Initial treatment:

1. Permethrin should be applied to hair that has been thoroughly dried.
2. Allow contact between hair and medication for a full 10 minutes, then rinse the medication from the hair with water and dry. Begin combing after about an hour.
3. Repeat the Permethrin treatment in 1 week.

If Nix fails to irradicate head lice prescription strength 5% permethrin can be used. A prescription is required in order to obtain this medication. This drug is applied to shampooed and dry hair, left over night under a shower cap or similar cover and the hair is shampooed the following morning.

Secondary treatment:

• Combing the hair to remove nits is a vital component of any treatment. Removal can be facilitated by wetting the hair thoroughly with 50% vinegar and 50% water before combing. Special fine toothed combs, available at pharmacies, are much more efficient than ordinary combs or brushes.
• All members of the family should be treated. Clean items that may harbor and thus transfer lice: wash linens, pillows, towels, clothing and hats in hot water. Rugs, car seats, etc. should be vacuumed thoroughly.

Prescription medication:

• If the remedies noted above fail to control lice it is imperative that sources of reinfection be controlled. Various medications, including 5% permethrin, requiring a prescription can be used for resistant cases. Consult your child's physician for a prescription and treatment plan.

November 2001

©2002 South Valley Pediatrics
page updated April 7, 2002