Common signs and symptoms of head lice may include: 
Itching. The most common symptom of head lice is itching on the scalp, neck and ears. This is an allergic reaction to louse bites. When a person has head lice for the first time, itching may not occur for 4 to 6 weeks.
Lice on scalp. You may be able to see the lice, but they're often hard to spot because they're small, avoid light and move quickly.
Lice eggs (nits) on hair shafts. Nits stick to hair shafts and may be hard to see because they're very tiny. They're easiest to spot around the ears and the hairline of the neck. Empty nits may be easier to spot because they're lighter in color and further from the scalp. However, the presence of nits doesn't mean there are live lice.
Sores on the scalp, neck and shoulders. Scratching can lead to small, red bumps that may sometimes get infected with bacteria.
