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Head Lice - Non-Toxic Head Lice Treatment: Tug That Bug
Careful combing is the only safe method of delousing. But it requires patience, diligence, a keen eye—and a sense of humor.
Pediculus humanus caitis, aka the head louse, is a tiny insect that lives on the human scalp, where it feeds on blood and lays eggs on hair. Nits, as the eggs are known, stick to the hair shaft but can be removed by careful combing, the only control method that is kind to human health and the environment.
Begin evicting the unwelcome visitors by combing hair into sections with a wide-tooth comb. Apply hair conditioner to each section and thoroughly comb it through with a fine-toothed nit comb, starting at the scalp and working outward. Examine each section of the scalp carefully and use tweezers to painstakingly remove remaining bugs and eggs.
Even a thorough session will need to be repeated in three days and then again in 10 days to insure that the lice are eradicated. Once away from the scalp and body heat, lice and nits will die in approximately 48 hours.
As for the combs, clean them in hot water and dry them on a towel. Place used towels in a closed bag to wash later.
To kill loose pests, washable items should be cleaned in hot water and dried at high heat.
Items that cannot be laundered can be deloused if stored in plastic bags for a few days. Upholstered furniture, carpets and rugs should be vacuumed.
Home insecticides are dangerous and unnecessary: Do Not Spray! Anyone can become infested with head lice, but children and people in institutions are most susceptible. As a preventative measure, children should be taught to avoid direct head-to-head contact or sharing hats and brushes when away from home.
LICE AND INSECTICIDE RESISTANCE
Common methods for treating head lice infestations include the use of insecticides such as Kwell, NIX, and RID. Head lice continue to develop a resistance to the active ingredients of these trade pediculocides. The National Pediculosis Association averages 50 calls a day from parents and health professionals reporting product treatment failures. Lindane (Kwell) is an organochlorine insecticide, that has commonly been used to treat head lice over the past 50 years. Use of lindane to treat head lice is not advised for two reasons. As mentioned above head lice is increasingly growing resistant to lindane. Lindane is also very toxic to humans. Lindane has been identified as neurotoxic and carcinogenic. Lindane is a moderately toxic compound via oral exposure. Acute effects may include mental/motor impairment, convulsions, increased respiratory rate and/or failure, and dermatitis.
Head lice have also developed a resistance to products such as Clear containing a pyrethin insecticide, and to Nix and Rid which contain permethrin, a pyrethroid insecticide. Pyrethrins, and pyrethroids are insecticides thought of as a less-toxic alternative to lindane. Pyrethrins are a naturally derived compound from a variety of chrysanthemum, and are generally regarded as safe. Pyrethroids are synthetic pesticides, having a chemical formula similar to pyrethrins. Head lice have grown resistant both to pyrethrin, and pyrethoid insecticides.
With a growing resistance to many chemical formulations, it is becoming more difficult to treat head lice using insecticides. The Food and Drug Administration recently approved the use of malathion for treatment of head lice as of April 1999, under the trade name Ovide. Malathion is an organophosphate insecticide which poisons humans and insects in a similar fashion by effecting the central nervous system. Malathion inactivates the nerve enzyme acetylcholinesterase. Symptoms of acute exposure to malathion may include the following, numbness, tingling sensations, headache, nausea, blurred vision, sweating, and difficulty breathing. These effects depend on product purity and route of exposure.
If an individual has attempted to use a product containing one of these insecticides and it has shown to be ineffective, do not reapply or try to find a stronger dosage. These chemicals are highly toxic and will not work due to the resistance attained by the head lice. Lice should die within 10 to 30 minutes after treatment of pyrethrin or permethrin.
LIFE CYCLE
Head lice are exclusively external parasites to humans, they have not been known to thrive on other mammals. Each female produces about 68 eggs in a 24 hour period, and can produce up to 50 to 300 eggs total. Eggs hatch within 7 to 11 days. Developing lice take 8 to 9 days to become an adult, after an additional day females can begin to lay eggs. Adult head lice live 9 to 10 days therefore the total life span is at least 25 days.
