If a little permethrin wasn't effective, neither was a larger dose. Some prescribed medications simply contain a higher concentration of permethrin. If you have permethrin-resistant lice, then it's best to try something else. Alternatives to permethrin include pediculicides containing lindane and malathion, both available by prescription. It was felt that the most critical action to take to end a head louse infestation, regardless of the use of any pediculicide is to practice good, anti-louse grooming.
Special combs are available for combing living lice and their eggs from the scalp and hair.
However, because the effectiveness of these combs depends on closely spaced teeth, they are difficult or impossible to use with some hair types or styles. These combs are of limited use for people with curly, coarse hair, or for those with braids or other styles that can't be combed through. This study did not address the prevalence of permethrin-resistant lice in the United States. Research to assess the extent of this problem is currently under way. These should be ruled out before resistance is assumed.