I have had it a few times- dont bother with the medicated shampoo, and the combs that come with them will probably rip out hair. get a comb with circular metal teeth like this: http://www.headlice.org/licemeister/index.htm
in fact, that one is a wonderful brand, all i ever used when I had lice. my mom diligently combed for about a week, and there were less and less each day until there were no more. i also use it if I want to get bits of stuff out of my hair.