A very itchy scalp. An allergic reaction to the saliva of lice causes itching, but only after an initial exposure period. A child who has never had lice won’t start itching until several weeks into the infestation. But when he starts to scratch his head with vigor, or reports a tickly feeling, it’s time for a lice check.
Nits. The tiny un-hatched lice eggs are about the size of a pinhead and are tan-colored if they are alive or darker if not (if hatched, their discarded shells are white and more visible). Unhatched, they are usually attached to the hair close to the scalp and are difficult to remove (hence the term nit-picking -- more on that later!). Nits, which don’t move, are usually easier than actual lice for a parent to detect.
Adult lice in the hair. Look for tan-colored or brown bugs about the size of a sesame seed. They frequently hang out in the hair behind the ears, and on the hair above the nape of the neck and will crawl quickly away from light. If your child doesn’t have a lot of them, they might be hard to spot.
Because it is easy to mistake dandruff or other debris in the hair for lice, experts recommend getting a diagnosis from your pediatrician or the school nurse before starting treatment.