Just to put things into perspective, Nix Lice Shampoo has 4 times more Permethrin than Raid Yard Guard and Rid Lice Shampoo has 8 times more Permethrin than Hartz 2 in 1 Flea shampoo.

For more on Permethrin, click here.

About Lice Shampoos and Super Lice

Are you still fighting head lice after using the drugstore brand treatments? Head lice is an increasing problem because Pediculicides, the shampoos used to treat head lice, are becoming less effective and lice resistant. A new form of resistent lice coined "Super Lice" are surviving these drugstore lice treatments. Historically, a family might experience a lice outbreak once in a lifetime, but in recent year many experience repeat occurances as a result of the Super Lice phenomena. Women who are pregnant or breastfeeding should not use head lice medications. Pediculicides contain pesticides called Permethrin. Never use products containing Lindane, a powerful neurotoxin banned for use in the United Kingdom and given unfavorable reviews by Consumer Reports. The National Pediculosis Association agrees that the mechanical (manual) removal is the safest and most effective way to remove nits and lice.

Science News

Four Out Of Five Head Lice Resistant To Common Treatment

ScienceDaily (June 14, 2006) - Four out of five head lice are resistant to a common treatment used to eradicate them, finds a study of Welsh schoolchildren, published ahead of print in the Archives of Disease in Childhood.

The authors used nit combs on a random sample of almost 300 000 primary schoolchildren at 31 schools spread across the five health authorities of Wales. All lice collected as a result of the screen were tested for resistance to pyrethroids, including measuring increased amounts of enzymes, such as glutathione transferases, monooxygenases, or esterases. Around 80% of 316 lice tested were resistant to the treatment, equating to resistance to four out of five head lice affecting primary schoolchildren in Wales, say the authors.