Head lice

Updated 20 January 2016

Diagnosing head lice

Diagnosing head lice can be tricky as both lice and nits can be tricky to spot, especially in thick hair. Finding any live lice in your hair constitutes a diagnosis.


A doctor would usually diagnose head lice simply by examining your head.

By using a special light called Wood's light, the nits can be made more obvious, appearing pale blue.

Using a fine-toothed comb is another effective way of identifying head lice. Comb from the crown of your head downward over the scalp at least twice.

 However, finding nits this way doesn't mean that there is a live active infestation. The best way to identify an infestation is if you find a live louse.

If you do find live lice, aim to treat the infestation as quickly as possible. If you have nits but no visible lice, it may be worth treating yourself any way in case the infestation is active.

Read more:

Treating head lice

Symptoms of head lice

Causes of head lice