Can a hair dryer kill lice?

It is unlikely you will completely eliminate head lice using a hair dryer without damaging your scalp or hair in the process. Even professional services that rely on heat devices with carefully calibrated temperature and airflow manually comb for 30-60 minutes or more after they use the device. If you are tying to treat lice on your own, get a professional quality metal lice comb, some hair conditioner, and start combing regularly.