Lice Resistant to Common Treatments
"I do think there is a problem with permethrin-resistant lice, but no one knows how large the problem is," Sharon Raimer, MD, tells WebMD. " Until we know, permethrin is still a reasonable treatment with which to start because it is safe and easy to use." Raimer is a professor in the department of dermatology at the University of Texas Medical Branch in Galveston.
However, other experts say that research convinced them that most permethrin products are probably ineffective. Jerry F. Butler, PhD, an entomologist at the University of Florida, who reviewed the study for WebMD, says the research shows "massive failure" of permethrin and confirms what Florida officials have long suspected.
"I think this is groundbreaking work," adds W. Steven Pray, PhD, RPh, who also reviewed the study for WebMD. "I have always seen resistance as a problem." Pray is professor of nonprescription products and devices at the School of Pharmacy at Southwestern Oklahoma State University in Weatherford.
Drugstores are often the first place parents or other adults run to after getting a note of a lice spread at school or finding a louse on a child. Therefore, pharmacists have a big role to play in educating parents, schools, and other health care providers about the proper way to fight lice, Pray adds. The message that he tries to get across to consumers and pharmacy students is that the weapons in the battle against lice are fingernails and a comb -- no chemicals, oils, salves, shampoos, or shower caps.
"We don't recommend Nix and Rid anymore, because of the resistance issue. I get people who look at me over the counter and tell me, 'I have used these six, seven, 10 times. I promise you I am using them right. And still I see lice.' They are using them everyday!" says Pray.
"And I tell them right off the bat, 'Let's get away from pesticides completely, and just go into combing,'" he says. "It is more effective to comb. All you need is a good comb and it doesn't involve any danger. Otherwise you are putting pesticides on the child's head, repeatedly. Even once is too much for me. And all we are doing is setting up more resistance."