Interior Health Instructions Head Lice

How to check for head lice
What you need:

Bright light

Regular comb

Metal lice comb

White hair conditioner (this colour helps to make the lice easier to see)

A magnifying glass can be helpful

Paper tissues (white is best as it gives a good background to see what is removed from
the hair)

Plastic bag for garbage
What to look for:
You are looking for both live lice and lice eggs, also known as nits:

Adult lice are 2-4 mm long, about the size of a sesame seed. Lice move quickly and can
be difficult to see. Lice tend to be reddish –brown in colour after feeding, but can also
match their colour to the hair they are in.

Lice eggs (nits) are shaped like tiny tear drops about the size of a poppy seed. They are
glued firmly to the hair and will not move unless you pull them off with your fingernails or
a nit comb.
Live lice on a nit comb next to hair strand, highly magnified.
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What to do when checking for head lice:

Apply a generous amount of conditioner to dry hair, soaking the scalp to the ends of the
hair. Conditioner stuns the lice for about 20 minutes, and this makes it easier to find
them.

Remove tangles in hair with a regular comb.

Start behind the ears and comb the hair section by section. Separating the hair with
clips or bobby pins is helpful.

Place the lice comb against the scalp and pull through to the end of the hair.

With every stroke, check the comb for lice and wipe it off on a tissue. Looking at what is
on the tissue helps to identify if you are finding lice or just regular hair debris (such as
dandruff, skin flakes, dirt).

Place used tissue in a plastic bag (when finished tie off bag and toss in outdoor
garbage).

Repeat the process several times moving around the whole head. Work section by
section, so that the whole head of hair is combed through. It will take at least 15 minutes
to do it properly.

Be sure to clean the combs thoroughly and disinfect them before using them on another
head (for example, soak for 1 hour in rubbing alcohol or for 10 minutes in water heated
to 55 degrees Celsius).
If you find head lice:

If you find live lice, you have a confirmed case that should be treated

If you only find nits (lice eggs) and they are close to the scalp (less than ¼ inch or 6 mm)
you have a probable case of lice. If your child has not been treated in the last month
you should treat for head lice now. (Nits found further away from the scalp are probably
dead and do not require treatment).

Nits and normal debris in the hair are hard to tell apart! One way to test if what you
are seeing are truly nits is to try and move them. Lice nits are cemented to the hair and
will not move without being pulled off by fingers or a nit comb. If what you are finding
moves easily, or flicks off easily, it is not a nit, and does not need to be treated.
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
If head lice are detected and a drug store treatment is going to be used, make sure that
all conditioner is washed from the hair before starting the treatment.

Check everyone else in the household for lice, even if they do not feel itchy.

Treat everyone in the household who has a confirmed case on the same day. You have
choices in how you treat head lice; you can buy treatments at the drug store or choose
to wet-comb the hair. There is more information on treatment available here:
https://www.interiorhealth.ca/YourHealth/SchoolHealth/HeadLice/Pages/default.aspx
Magnified louse and nits cemented to hair.
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