OTC insecticides used to kill lice, such as NIX and RID, are becoming less useful, according to the WSJ.
The most common prescription treatment, Ovide, still works in the US, but in the UK lice have developed a resistance to malathion, the active ingredient.
From the WSJ:
A number of new treatments are in the pipeline, but are still a ways off from approval by the U.S. Food and Drug Administration. In the meantime, many people are searching for new ways to kill these pests — which affect six million to 12 million people each year in the U.S., occurring in all areas of the country and across socioeconomic strata.
Bayer HealthCare, the maker of RID, says its product is effective when used as directed — including combing out the hair between two applications of the shampoo. The company says it believes any problems with efficacy and reinfestation are linked to incorrect application.
So-called nit-picking services, where someone manually combs out the lice and their eggs, are another alternative that has been growing in popularity. New salon-style providers have been popping up around the country — and some make house calls. But such services can be expensive, costing hundreds of dollars. Hair Fairies, with salons in Los Angeles, San Francisco and New York, charges $300 a person, according to Maria Botham, Hair Fairies founder. Other such services include Lousey Nitpickers, which operates in Southern California and charges $100 and hour, and Lice Fighters, which makes trips throughout New York, New Jersey and Pennsylvania, for $200 a head.
A Head Scratcher: How to Get Rid Of a Pesky Parasite [WSJ]