Head Lice: All you need to know

by | Dermatology, Pharmacy Care

Head lice (Pediculus humanus capitis) are small wingless insects that live in your hair

General Information

Headlice (Pediculus humanus capitis) are small wingless insects that live in your hair. They are a brownish grey colour, measure just a few millimetres long (2.5 to 3.5 mm) and have six legs with claws to hold onto hairs. Head lice feed on blood from your scalp and are often most noticeable behind the ears and at the nape of the neck. They can be difficult to see on the scalp as they move very quickly when the hair is disturbed.

Lice cannot fly or jump, but they can ‘trapeze’ or crawl from person to person when there is close contact between heads (and possibly through sharing hairbrushes or combs).

Female headlice lay eggs called nits, which appear as tiny white specks on hairs, close to the scalp. They lay about 6 to 8 eggs every day. They lay the eggs close to their food supply – the scalp. The eggs hatch after 7 to 10 days. The empty egg cases can also be seen in the hair and are found slightly further away from the scalp. It is important to check behind the ears and at the nape of the neck when looking for a lice infestation. That is where the nits are often seen. They are attached firmly to the hair and are hard to remove or slide along the hair shaft. This is in contrast to dandruff, which is easy to slide along the hair shaft.

How are head lice spread?

Because they cannot fly or jump, head lice must come in close contact with another person’s hair or head to spread. This can be done by sitting or lying next to a person with head lice, or using the same hairbrush, comb or hat. Head lice infestations occur most frequently in schoolchildren because they tend to be in close personal contact with each other and to share brushes and combs, but they can spread to adults. Head lice are not associated with a lack of cleanliness (in fact, some believe that lice prefer clean hair).

Symptoms of head lice

Head lice may cause the scalp to itch, although often there are no symptoms. An active infestation of head lice is diagnosed by looking at the scalp and hair and either finding a live insect on the scalp or finding an egg (a nit) within 1.5 cm of the scalp (older eggs are found more than 1.5 cm from the scalp).

Often there are no obvious signs of infestation. There may be blood spots, a rash or scratch marks around the hairline and neck from itching. Sometimes there is no itch at all. These symptoms appear only after several weeks of infestation, when the body develops an allergic reaction to the saliva of the lice.

Head lice are not a sign of dirty hair or poor hygiene. They are just as likely to be found in clean hair.

Wet comb technique to find lice

To help detect head lice, you can use the wet comb technique. Simply apply any brand of regular hair conditioner to dry, untangled (brushed) hair. This stuns the lice for about 20 minutes. Then comb the conditioner through to the ends of the hair using a fine-toothed lice comb. Wipe the combings onto a tissue; inspect the tissue for lice and eggs as you go (live eggs will ‘pop’ when squeezed between the fingernails). If any lice or live eggs are present you need to treat the infestation as described below.

How are head lice treated?

If you find lice or live nits in the hair or in the combings after using the wet comb technique, you will need to treat the infestation.

Some cases can be treated by wet combing every day for 10-14 days until no lice are found, but this method has only about a 40 per cent success rate.

Alternatively, a special shampoo or lotion can be used. Speak to your pharmacist for advice about which treatment to use. Follow the directions on the package carefully using a clock to time how long the treatment should be left on. Unfortunately there is a high degree of resistance to many of the available lice treatments. Do not be tempted to use kerosene, insecticides or methylated spirits. Many treatments can irritate the scalp. While it does have antiseptic properties, there is no clear evidence that tea tree oil is an effective treatment for lice.

The shampoo or lotion will need to be applied twice. This is because no head lice treatment kills the eggs as well as the lice. Treatment is generally repeated after 7 to 10 days to kill the newly hatched lice from eggs that have survived the first application. Wet combing should be performed twice in between applications to remove any eggs, and a day after the second application to check the effectiveness of the treatment.

If the lice are resistant to a particular shampoo or lotion, the treatment will need to be repeated with a different formulation. If several have failed you may need to fall back on the time-consuming comb and conditioner method.

Nits and lice may be found on items that the affected person has been using, such as bedding. They can be removed by machine washing and drying on the hottest setting. You can treat combs and brushes by soaking them for at least 5 minutes in hot water (more than 55 degrees Celsius).

An alternative to washing in hot water is to carefully seal contaminated items in plastic bags for about 14 days, which kills the lice because they are separated from their food source.

Check for head lice on the scalps of family members and close contacts. Only treat if an active infestation is found — there’s no need to treat everyone who has been in contact with the person who has had head lice.

See Your Pharmacist or Medical Professional

  • if you have broken skin or sores on your scalp
  • if you are unsure of the problem (skin conditions such as dandruff and psoriasis can be confused with head lice)
  • if the person with head lice is a child under six months old
  • if you are pregnant, breastfeeding or have eczema or asthma
  • if you still have head lice after treatment; check you have repeated the treatment according to the product directions

Treatment Tips

  • some products need reapplying to kill further lice that hatch from nits missed by the first treatment. See individual products for directions
  • check for and treat all affected family members at the same time
  • avoid getting the products in your eye
  • some products may affect permed, coloured or bleached hair
  • wash all hairbrushes and combs in hot water (60 degrees C)
  • head lice do not survive long once away from the body
  • washing clothing, bedding and towels is often recommended as part of treatment. Wash pillow cases on a hot cycle.
  • use a fine-tooth nit comb to remove dead lice and nits
  • tell your child’s school or preschool

Advice for preventing head lice

  • avoid sharing hairbrushes, combs and hats
  • avoid touching heads together
  • keep long hair tied back or cut hair shorter
  • check your child’s scalp and hair each week
  • preventative use of head lice products is not recommended because it can make head lice resistant to treatment
  • check for head lice by applying hair conditioner to dry hair and using a fine-tooth comb to look for lice or eggs. Repeat this combing, wiping the conditioner onto tissue to check for infestation
  • until a live louse is seen, an active infestation cannot be confirmed. The presence of nits (eggs) does not necessarily indicate an active infestation. To minimise resistance, do not use treatments until a live infestation has been confirmed.

Treatment Options

Anti-lice (anti-parasite) products

e.g. maldison (KP24 Medicated Lotion and KP24 Medicated Foam)

  • kills head lice and nits
  • apply the lotion and foam as directed: use a fine-tooth comb afterwards to remove dead lice
  • don’t use a hair dryer after applying the lotion; allow to dry naturally
  • avoid contact with eyes, mouth and inside the nose
  • re-treat after 7 days

e.g. permethrin (Quellada Head Lice Treatment)

  • treatment may require two applications 7-10 days apart
  • apply Quellada to damp, dry hair, leave on for 10 minutes, wash out then comb through
  • avoid contact with eyes, mouth and inside the nose

e.g. dimethicone (Hedrin Lotion and Spray, NitWits, NYDA Express)

  • kills lice by blocking the pores they breathe through, and by blocking their water excretion
  • apply Hedrin to dry hair, leave for 15 minutes, repeat in 7-10 days. NitWits Solution should be applied to dry hair, and left for 20 minutes.

Combination products

e.g. pyrethrins + piperonyl butoxide (Banlice Mousse, Paralice, Pyrenel Foam)

  • repeat treatment after 7 to 10 days to kill any new lice
  • avoid contact with eyes, mouth and the inside of the nose
  • apply the mousse or foam to dry hair, massage in until wet, leave for 10 minutes, wash with regular shampoo and remove lice with a fine-tooth comb
  • apply the spray to the whole scalp (do not cover), leave for 30 minutes then rinse with warm water. Use a fine-tooth comb to remove lice

Products containing natural ingredients

e.g. herbs and/or essential oils, acetic acid, benzyl alcohol (Lice Breaker Naturals Head Lice Solution with Conditioner, Lysout 1 Gel, Lysout 2 Spray, Moov Head Lice range, NeutraLice range, QuitNits, Thursday Plantation Tea Tree Headlice kit, Euky Bear Blitz Nitz)

  • Moov preparations contain a mixture of essential oils, including eucalyptus oil, which kills head lice and eggs
  • Moov preparations should be applied as directed and the treatment repeated after 7 and 14 days
  • Lice Breaker should be left on hair for at least 20 minutes, and repeated in 7-14 days
  • Lysout Gel and the Neutralice range should be applied to towel-dried hair, left for 10-15 minutes, and repeated in 7 days
  • Lysout Spray is to be sprayed onto the head in the morning before combing through thoroughly
  • Thursday Plantation should be applied to dry hair, left for 20 minutes and repeated in 7 days


e.g. Lice Blaster Comb, Moov Head Lice Combing Conditioner With Comb, Neutralice Nit Comb, NitWits Headlice Comb, Surgipack Nit Comb

  • use to remove dead lice and nits after treatment
  • use for wet combing to remove live lice and eggs
  • use with a conditioner to aid combing

More Information

Availability of medicines

  • GENERAL SALE available through pharmacies and possibly other retail outlets.
  • PHARMACY ONLY available for sale through pharmacies only.
  • PHARMACIST ONLY may only be sold by a pharmacist.

Search myDr for Consumer Medicine Information