PHILADELPHIA (CBS) – Parents and schools battling head lice are finding the critters are winning.

The first line of defense can be found over the counter, at the local pharmacy.  But Dr. Stephen Aronoff, chairman of the department of pediatrics at Temple University School of Medicine, says the lice are becoming resistant.

Parents will know they need a more powerful medication, he says, if the usual treatment is a bust.

“Eight to 12 hours following the application of the material they are using, they really need to check and see if they are still seeing lice that are active and moving.  And if they do, they need to be concerned that they have an infestation with a resistant strain,” he says.

Dr. Aronoff adds that there are two FDA-approved prescription medicines that are effective, but they do have side effects and must be prescribed by your doctor — and used carefully.

Reported by Lynne Adkins, KYW Newsradio 1060

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