100% works and worth the 1 hr and 45 min drive from longview. Watched the lice die and fall out of my daughters hair in front of my very own eyes. My daughter has long beautiful curly hair and we did not want to spend 4 hrs every night nit picking. The time and money it would have cost to nit pick and retreat the hair for the next month does not compare to the 1 hr treatment and the guarantee that the lice and nits are gone. I highly recommend this. Don’t even try the over the counter treatment products that are 68% effective. This is 98.2% , no brainer.