Most head lice shampoos that contain coconut oil also contain anise seed, ylang ylang and isopropyl alcohol. These shampoos have a very strong licorice scent due to the anise seed. The coconut oil kills the adult lice and the newly hatched nymphs, but not the eggs, so combing is still necessary. Shampooing and combing should be repeated a minimum of four times, with each shampoo being done three days apart.