Treatment of Pediculosis Capitis (Head Lice) by Mark B. Levin, M.D. The Pediatric Group, P.A., Princeton

This is the twentieth article in a series written for Princeton Online. Click here for an archive of other articles.

Now that school has begun, children will be sharing their ideas, their pencils, their germs and their head lice. We hope sharing of these last two items is minimal during the year, but in case you encounter head lice, the following outline provides useful information for treatment.

A. Background:

1.Humans are the only host for this infestation.
2. Head lice are different from scabies and from pubic lice.
3. The time from egg to egg-laying adult is about one week.
4. The eggs (nits) are laid glued to the base of a hair shaft, typically around the back of the head first, but spreading to the top and front as the infestation increases.
5. Although a source of social disruption, head lice cause no human disease.
6. Head lice have existed for as long as civilization has been around (maybe longer). We know of a professional nit-picker in Brooklyn, although we cannot vouch for her effectiveness. Folk treatments include slathering shortening (butter or lard) into the hair, leaving it on for one to three days, then washing it out (I am not sure how to get it all out!).

B. Treatment:

1. Children under one year of age and pregnant women should consult the doctor before undertaking any treatment
2. Wash the hair with any non-conditioner shampoo
3. Towel dry the hair
4. If a nit loosener is to be used (a half water/half vinegar solution or Step 2®), it should be used at this point
5. Massage Nix Creme Rinse® (1% permethrin) into scalp and hair and let it stay on for 10 minutes. Some people may experience itchiness of the scalp after using Nix®. We do not recommend other brands because Nix® is the only one with a residual 7-day protective effect. Permethrin is an extract of the Chrysanthemum family flower. It is not absorbed through the skin and is non-toxic topically.
6. Rinse out the Nix® and blow dry the hair
7. Carefully and thoroughly remove all nits from the hair shafts with fingernails or tweezers. A fine tooth "nit comb" may be helpful, but is not totally effective. Nit removal is critical to successful treatment
8. Do not use conditioner for one week as this may inactivate the residual effect of the Nix®.
9. Wash linens in hot water
10. Any clothing that has been in contact with the hair must either be washed in hot water or placed in a knotted plastic bag for one to two weeks. Dry cleaning does not kill the nits.
11. Brushes and combs can be soaked in hot water, in bleach or in Nix®.
12. Upholstered furniture and rugs should be vacuumed
13. Nix® leaves an protective residue on the hair for about one week. Repeated treatments are usually not needed unless there is re-exposure.
14. Relapses due to re-exposure may be re-treated as above. For cases of non-clearance, other modalities such as Elimite Cream® (a 5% overnight permethrin cream), Kwell Shampoo® (containing lindane, a potentially toxic chemical), Ovide® (0.5% malathion) and Mectizan® or Stromectol® (ivermectin) or cotrimazole (a sulfer based antibiotic) administered orally should be discussed with your physician regarding use. Ivermectin and cotrimazole kill lice, but not the nits.

Dr. Mark B. Levin 

Dr. Levin has been a member of the staff at The Pediatric Group since 1977. Currently an attending Pediatrician at the Medical Center at Princeton, he has been Chairman, Department of Pediatrics, Medical Center at Princeton, 1984 to 1986, 1989 to 1992, and past President, Medical and Dental Staff, Medical Center at Princeton, 1987 to 1988. Dr. Levin has served on numerous Departmental and hospital committees. He has published original articles both while at Upstate Medical Center in Syracuse and at The Pediatric Group. He has a wife and three children. Dr. Levin enjoys alpine skiing, jogging, hiking and camping, travel, computers and racquetball.