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Head lice alternatives to Rid, Nix and permethrins--and resistance to treatment

When students return from summer travel, so do those anoying head lice.  Reports of head lice have surfaced at all elementary, charter and private schools lately. While not proven to transmit disease, no-nit policies of local schools can disrupt student attendance. But there is no need to expose a child's head, and bloodstream to pesticides at all.  Over the counter chemicals such as permethrin and synthetic pyrethrins can have significant health effects.  More toxic and worrisome are the Rx only chemicals such as lindane (banned in Europe, Canada and California) and Malathion.  Of first interest to parents, head lice have grown reisitance to permethrin, pyrethrins, and lindane and  Malathion. For more information on their toxicity and  on head lice alternative treatments, look at www.beyondpesticides.org and search for head lice fact sheet or the above pesticides.

One alternative but very effective product available at some Rite-Aid stores and Walgreens but not yet CVS is LiceBGone, a shampoo made from vegetable enzymes.  It kills adult lice and dissolves the glue holding nits (eggs) to hair shafts.

The manufacturer's web site has more product information, endorsements from school nurses and MD's, etc. They are at: www.s-e-a.net
Here are the facts on pesticide resistance from Safe and Effective Alternatives, Inc., the manufacturer of LiceBGone

THE HARVARD STUDY - Published studies from the Czech Republic and Israel and findings from Harvard University support the theory that there are new strains of "super lice" that can survive pyrethrin and permethrin, the pesticides used in head lice shampoos. In the Harvard Study, lice collected from Cambridge, Mass., Boise, Idaho and the Philippines were placed on permethrin-soaked paper. The lice gathered from the Philippines (where such shampoos are not used) all died quickly. By contrast, the lice gathered from the US did not. Wall Street Journal 8/12/98 PYRETHRINS / PERMETHRINS - Natural pyrethrins were introduced into the US in the 1980s as a less-toxic alternative to lice shampoos containing lindane (Kwell, etc.). A number of pyrethrin formulations are sold over the counter, such as Rid, Clear, A-200 as well as many private label brands with the same formula. Lice that are resistant to pyrethrins are also resistant to permethrin products like Nix and pyrethroids (synthetic pesticides having a chemical formula similar to natural pyrethrins). As a consequence, the entire pharmacological class is becoming less valuable. Common Sense Pest Control Quarterly (B.I.R.C.) Fall 1998
The marketing of permethrin in Israel started in 1991. The first reports of resistance were in 1993, a time equivalent to 40 generations of lice. Similarly, resistance was reported within four years of introduction in the countries of France, the Czech Republic and Great Britain. PHYSICIANS - Because of resistance and product failure, some physicians have overreacted by prescribing repeated use of products, stronger formulas or longer application times. These practices should be discouraged! History indicates that lice eventually grow resistant to every effective insecticidal treatment used against them. When will we learn?

A brief history of lisce developing resistance to pesticides

DDT

The age of synthetic pesticides for lice treatment started with the synthesis of DDT in 1939. During World War II, DDT was used with great success when the population of Naples was dusted with it to stop the typhus epidemic. At that time, DDT effectively killed body lice. Less than 10 years later, during the Korean War, body lice could not be stopped with DDT due to the resistance they had developed. Head lice resistance to DDT was later seen in Britain in 1971. Today, head lice throughout the world remain resistant to this harmful pesticide.

LINDANE (Kwell)

Lindane is an organochlorine pesticide that has been used for lice treatment for about 50 years. It was used for chemical warfare in World War I but by luck (if you want to call it that), its efficiency for lice was discovered when soldiers were found to be lice-free after exposure. During the Korean War, when lice became resistant to DDT, the substitution of lindane, for a period of time, controlled them successfully.

Head lice resistance to lindane has been reported in many parts of the world, including Israel, Canada, Denmark, Malaysia and the US. Lice in the Netherlands had grown so resistant to lindane in 1978 that two treatments gave only a 65% cure rate. When it was introduced in the 1950s, one treatment given of the same formulation was 100% effective.

Click here to read the Biopestman's previous articles about keeping pests out of your home. Alan Cohen, the MPN Biopestman, is president of Bio-Logical Pest Management based in Washington, DC.