In many cases, head lice cause the scalp to itch. Iitching is not due to lice biting the scalp but by an allergy to the lice.
However, not everyone is allergic to head lice, so you or your child may not notice a head lice infestation.
Also, even if someone with head lice is allergic to them, itching can take up to three months to develop.
In some cases a rash may appear on the back of the neck. This is caused by a reaction to lice droppings.
Looking for head lice
It is difficult to see head lice, even when the head is closely inspected. Unhatched eggs or nits (empty eggshells) alone are not enough to diagnose an active head lice infestation.
This is because it can be difficult to distinguish between eggs and nits that are dead or alive. Nits also often remain glued to hairs after successful treatment.
To confirm an active head lice infestation, a louse must be found through a reliable, accurate, method, such as detection combing.
Read more about detecting head lice.
