Sherry
Our daughter a couple of years ago had lice three times. The school nurse who was also a friend told us that there is a new strain of lice resistant to common treatments. She told us to use olive oil. Rub it in the hair until sarurated. Leave it in a couple of hours use a fine tooth comb to comb out the nits. Then wash the oil out. It worked like a charm. I washed all the bedding and hairbrushes as usual. They never returned. Hope this helps.