I used cedarwood oil for lice. It is a essential oil that can be bought from most soap making supply companies, I got mine from a local soap and candle supply company. Keep in mind. It must be The real essential oil to work well. The cedarwood oil kills the lice, and dissolves the nit glue easily and also kills the eggs. It is totally non-toxic. I coated my granddaughter's head, left it on for 30 min. (Test a nit egg to make sure it releases easily) Worked like a charm, after fighting for a month with over the counter treatments. This put an end to the cycle.
Cedar oil it awesome for lice, bed bugs, fleas and on and on. It's completely natural, smells good and absolutely no side effects, of course unless you're allergic to Cedar oil. It's amazing. I use on the yard, the outside of house, the inside of my house, for fire ants, flies, gnats, mosquitos, in my dogs ears, on my dogs and cats. It's GREAT!!!! No ill effects on anyone or any animal in our home.