Pediculicide

Pediculicides are substances used to treat lice (Pediculus humanus capitus).

Today, insecticides used for the treatment of head lice include organochlorines (lindane), organophosphates (malathion), carbamates (carbaryl), pyrethrins (pyrethrum), and pyrethroids (permethrin, phenothrin, bio-allethrin).

Laboratory and clinical studies found that many of the pediculicides in the market are either not fully effective or are ineffective when they are used according to the instructions.

Pediculicides may rapidly lose their efficacy because of the development of resistance. Resistance of head lice to insecticides such as lindane, malathion, phenothrin and permethrin has been reported.

Ivermectin (which can be given orally) has been shown to reduce levels of louse infestation. Originally approved for onchocerciasis and strongyloidiasis,Ivermectin is now approved by the FDA for pediculosis.

Clinical studies of natural products are very limited, and most have methodological problems such as lack of a comparison group.

Certain proteases can have insecticidal effects. This process works through using naturally occurring enzymes similar to those within the insects themselves. These proteolytic enzymes cause the insect to hatch and molt prematurely, destroying the creature's exoskeleton. These enzymes are similar to those found in meat tenderizers and digestive aids. The benefits of this type of treatment is that the lice do not develop resistance and these products are less toxic.

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