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Study: Lice in many states resistant to common OTC treatments


CARMEL, Ind. — A new study published in the Journal of Medicine Entomology is showing that an average of 98% of head lice in 42 states have developed genetic mutations making them resistant to permethrin, the active ingredient in OTC lice medications. 


One of the contributing factors to the rise of treatment-resistant lice, according to specialty pharmaceutical company ParaPRO, is misuse as a result of self-diagnosis. In recent studies, as many as 69% of people self-treating with OTC lice products use more than the recommended dose to increase effectiveness. 


 “This newly published data supports what we’ve been seeing in our offices and clinics: an increase in treatment-resistant super lice,” said Dr. Chris Belcher of Peyton Manning Children’s Hospital at St. Vincent in Indianapolis, Ind. “It’s important that parents contact a clinician if they suspect their child has head lice. There are effective, non-pyrethrin, non-pyrethroid-based prescription agents that can be used if treatment with over-the-counter products … has been unsuccessful.”


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