Head lice are small, wingless insects that live, breed and feed on the human scalp. They do not carry or transmit disease. They have been around for millions of years and, in fact, predate human evolution. Direct contact is required for transmission from person to person. Lice will crawl from head to head without discrimination.
Head lice facts
A female louse will lay between three to eight eggs (nits) per day on the hair. The eggs are attached to the hair fibres within 1.5 cm of the scalp, and rely on warmth from the head to hatch. Head lice do not have wings or jumping legs, so they cannot fly or jump from head to head. They can only crawl.
People get head lice from direct head-to-head contact with another person who has head lice. This can happen when people play, cuddle or work closely together. Head lice are most common among children and their families. If your family has head lice, tell anyone who has had head-to-head contact with them, so that they can check and treat their family if needed. There is no need to treat the whole family, unless they also have head lice.
Concentrate on treating the affected person’s head. There is no evidence to suggest that you need to clean the house or the classroom. The only linen that requires changing is the affected person’s pillowcase.
The itchiness may not disappear immediately after treatment. Persistent itch is not a reason to repeat the treatment.
Finding head lice
Half of the people who have head lice never scratch their head, so itching is not a reliable sign. Lice can be hard to spot because they move quickly.
The easiest and most effective way to find head lice is to use the conditioner and comb treatment weekly. This includes:
- Step 1. Comb hair conditioner onto dry, brushed (detangled) hair. This makes it difficult for lice to grip the hair or run around.
- Step 2. Wipe the conditioner from the comb onto a paper towel or tissue.
- Step 3. Look on the tissue and on the comb for lice and eggs.
- Step 4. Repeat the combing for every part of the head at least four or five times.
- Step 5. If the person has been treated recently and only hatched eggs are found, you may not have to treat them again, since the eggs could be from the old infection.
- Step 6. If lice or eggs are found, the person should be treated.
Treatment for head lice
The two preferred treatment options available for initially treating head lice are the ‘conditioner and comb’ method and the use of an insecticide.
Using insecticide products
Any head lice treatment product you choose should carry an Australian Registered or Listed number.
If you use lotions, apply the product to dry hair. For shampoos, wet the hair, but use the least amount of water possible.
Head lice live in the hair and go to the scalp to feed. Therefore, head lice products must be applied to all parts of the hair.
Care should be taken when using these products:
- if you are pregnant or breastfeeding
- in children less than 12 months old
- in people who have allergies, open wounds on the scalp, or asthma.
All products can cause reactions. If you are unsure, check with your pharmacist or doctor.
Insecticide resistance is complex and common, so you need to check that the lice are dead. If the insecticide has worked, the lice will be dead within 20 minutes. If the lice are not dead, the treatment has not worked and the lice are resistant to the product and all products containing the same active compound. Find a product with a different active compound or speak to your pharmacist or doctor.
No topical insecticide treatment kills 100 per cent of the eggs, so treatment must involve two applications, seven days apart.
If you choose not to use an insecticide, the comb and conditioner method described above can be used every second day until no live lice have been found for 10 days.
Head lice combs
Head lice combs with long rounded stainless steel teeth, positioned very close together, are the most effective. However, any head lice comb can be used.
If the initial treatments have failed and live lice are still being removed with the conditioner and comb treatment, see your doctor for a referral for to a dermatologist for specialist treatment. This may involve the prescription of medication.
Preventing head lice
There is no product available that prevents head lice. However, tying long hair back and checking weekly for lice, using the conditioner and comb method, can help prevent the spread.
Where to get help
- Your doctor
- Local government health department
- Public Health, Department of Health Victoria Tel. (03) 9096 0000
Things to remember
- Head lice have been around for thousands of years and anyone can get them.
- Using the conditioner and comb method once each week will help your family control head lice.
- Head lice do not carry disease.
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Content on this website is provided for education and information purposes only. Information about a therapy, service, product or treatment does not imply endorsement and is not intended to replace advice from your doctor or other registered health professional. Content has been prepared for Victorian residents and wider Australian audiences, and was accurate at the time of publication. Readers should note that, over time, currency and completeness of the information may change. All users are urged to always seek advice from a registered health care professional for diagnosis and answers to their medical questions.