Live head lice grow to be about the size of a grain of rice, are dark-colored and like to scurry around a lot. The best way to tell if a person is actively infested with head lice is to find the little buggers hard at work. To find live head lice, separate the hair all the way down to the scalp and look for movement.
Unfortunately, head lice doesn't want to be seen, which would not be good for long-term survival. A second, less accurate way to identify head lice infestation is to look for the nits attached to the hair. Nits are shaped like teardrops and are lighter in color than the live lice. They don't come off the hair easily, which is one way to tell the difference between nits and dandruff.
Head lice lay their eggs on the hair follicle as close to the scalp as possible. It's the warmth of the scalp that keeps the nits alive, which means if the nits have not hatched by the time the hair grows more than half an inch, they probably won't hatch at all.
Head Lice TreatmentOnly active infestations need to be treated. If nits are found on hair within half an inch of the scalp, it may be an active infestation. If live head lice are found bustling about on the scalp, it is definitely an active infestation. If no live head lice are seen and the only nits are more than half an inch from the scalp, it's likely not an active infestation and no treatment is necessary.
Head lice are typically treated with a pediculicide (lice-killing) shampoo. There are two over-the-counter shampoos available: Permethrin and Pyrethrins, with piperonyl butoxide. If over-the-counter treatments don't work, there are prescription medications available through your doctor as well: Malathion and Lindane.