Researchers in Wales say over-the-counter remedies for lice aren't as effective as the insects have begun to mutate and are becoming immune.
Daniel Thomas of the National Public Health Service led a team of scientists that searched the heads of 4,000 Welsh kids and found four of five lice resisted removal treatments of the chemicals permethrin and phenothrin.
The Times of London reports an estimated 8 percent of children in all of Britain have lice, which have been able to either repel the once-poisonous treatments or are immune to it altogether.
While new products are intended to have the same effect, some more traditional methods may become the most effective.
Some of those methods include using special combs to search for and destroy the lice, special oils that repel the bugs or make the hair so greasy they fall out.
Copyright 2006 by United Press International
Explore further: Diabetes drug found in freshwater is a potential cause of intersex fish