Head Lice
Also known as Nits, Pediculosis capitis
This article is general health information for the selected condition. It is not a diagnosis and does not replace clinical judgement. If you have questions or need treatment advice, please consult a qualified healthcare professional.
What is head lice?
Head lice are small insects that live on the scalp and feed on blood. They spread by prolonged head to head contact, not by poor hygiene, and they cannot jump or fly. Diagnosis requires seeing a living louse, since eggs alone may be old and empty. Treatment is only needed for confirmed live infestation.
Causes
- Direct prolonged head to head contact
- Occasionally shared hats, combs or pillows
- Not related to cleanliness or hair washing
- Common in school aged children
Symptoms
- Itchy scalp, though many people have no itch
- A tickling sensation of movement in the hair
- Live lice seen when combing wet hair
- Eggs glued firmly to hair near the scalp
- Small red bite marks on the scalp or neck
- Difficulty sleeping from itching
Risk factors
- Age 4 to 11
- Close contact at school or in the household
- Long hair worn loose
- Sharing beds or sleepovers
Diagnosis
- Detection combing of wet conditioned hair with a fine tooth comb
- Finding at least one living louse confirms infestation
- Eggs alone are not enough, as empty shells persist after treatment
- Checking all household members at the same time
Treatment
- Wet combing with conditioner every few days for two weeks
- Dimeticone or other physical insecticide lotion
- Repeat the treatment after seven days to catch newly hatched lice
- Treat all affected household members on the same day
- No need to treat people without live lice
Self care
- Comb wet conditioned hair from roots to tips with a detection comb
- Wipe the comb on tissue after each stroke to check for lice
- Repeat on days 1, 5, 9 and 13 to break the life cycle
- Follow lotion instructions exactly, including leaving on long enough
- Wash bedding and hats on a hot cycle, though this is a minor route
- Tell close contacts so they can check too
When to see a doctor
Book an appointment if:
- Treatment has failed twice with correctly used products
- The scalp is red, weeping or crusted
- Swollen glands in the neck
- Lice in eyelashes or eyebrows
- Uncertainty about whether lice are present
- Pregnancy or a young baby needing treatment advice
Some symptoms need emergency care rather than an appointment. See the warning signs listed above.
Prevention
- Tie long hair back at school
- Check hair weekly with a detection comb if outbreaks are common
- Avoid head to head contact during play
- Do not share combs, brushes or hats
- Treat everyone affected in the household simultaneously
Outlook
Head lice are harmless and clear completely with correct treatment, though reinfestation is common in school settings. Treatment failure usually reflects an incomplete course or missing the second application, not resistance. There is no need to keep children off school.
Common questions
Do head lice mean poor hygiene?
No. Lice spread by head to head contact regardless of how clean the hair is, and some evidence suggests they attach more easily to clean hair. It carries an unfair stigma that discourages families from mentioning it.
Should my child stay off school?
No. Children can attend as normal. Treat on the day you find live lice and let the school and close contacts know so others can check.
References
Important: Dard AI is not a medical device and does not diagnose, treat, or replace clinician judgement. This article is general information only. Always consult a qualified healthcare professional about diagnosis and treatment, and seek emergency care for severe or rapidly worsening symptoms.