The most common signs and symptoms of head lice include a crawling sensation on the head and scalp, seeing light brown bugs that resemble sesame seeds on the head and finding yellow or brown eggs the size of a pinhead, according to the American Academy of Dermatology, or AAD. Patients may also experience an itchy scalp, swollen lymph nodes and pink eye when they have lice.
It often takes weeks before the itching sensation begins after the lice have infested the scalp, according to AAD. Lice are visible to the naked eye and have three forms which include the egg or nit, the nymph and the adult. Adult louse have six legs and live for approximately 30 days on the scalp of an individual. Lice can live up to 2 days after they have fallen off the scalp. Lice most commonly infest the scalp, but they can also be found on eyebrows and eyelashes, as noted by the Centers for Disease Control and Prevention.
Head lice is most commonly spread through direct contact and rarely spread when inanimate objects are shared from one infested person to a non-infested person. Head lice can be treated by washing the hair with special medicated shampoos that contain 1 percent permethrin, as reported by the National Institutes of Health's MedlinePlus. It is important to follow the instructions of the medication thoroughly to ensure the lice infestation is completely eradicated.