Skin
Medicines for Head lice (nits)
Tiny insects that live on the scalp and lay eggs (nits) glued to the hair, spread by head-to-head contact — itching is common but not always present; diagnosis depends on finding a live louse, and treatment is with a physical insecticide lotion or wet-combing, repeated after about a week, treating only people who have live lice.
Education and reference only. This explains which medicines are used and why, in plain language — it deliberately contains no doses and is not a substitute for advice from your doctor or pharmacist. Always discuss your own treatment with a qualified clinician, and check the BNF and the product labelling for prescribing detail.
Quick answer
What is Head lice (nits)?
Head lice are tiny, wingless insects that live on the human scalp, feeding on blood and laying eggs that they glue firmly to the base of hairs. The empty eggshells and eggs are often called nits.
- How it is treated: The first and most important step is to confirm that there are genuinely live lice present, because treatment should only be used for people who actually have them — not as a precaution.
- Self-care: Checking heads regularly by detection combing on wet, conditioned hair helps spot lice early; treating only people who have live lice, repeating treatment after about a week, and checking close household contacts (treating only those who also have live lice) are the practical mainstays.
- When to seek help: Head lice can almost always be managed at home, but it is worth asking a pharmacist or GP for advice if you are unsure whether what you are seeing is genuinely live lice, if treatment does not seem to be working after you have completed a course and the repeat treatment, or if the scalp becomes very sore, weepy or shows signs of skin infection from scratching.
What it is
Head lice are tiny, wingless insects that live on the human scalp, feeding on blood and laying eggs that they glue firmly to the base of hairs. The empty eggshells and eggs are often called nits. Lice spread from person to person through direct head-to-head contact, which is why they are common among children who play closely together, and they do not jump or fly. Many people assume an itchy scalp always means head lice, but itching is caused by a reaction to the lice and is common rather than guaranteed — some people have lice without any itch at all. Importantly, having head lice is not a sign of poor hygiene or dirty hair; lice are happy on clean and dirty hair alike. They are a nuisance rather than a danger, do not spread disease, and there is no need to keep a child off school. The key to dealing with them is to confirm that live lice are actually present and then to treat thoroughly, including repeating treatment to catch any that hatch afterwards.
How it is treated
The first and most important step is to confirm that there are genuinely live lice present, because treatment should only be used for people who actually have them — not as a precaution. This is done by detection combing: working through wet, well-conditioned hair section by section with a fine-toothed comb and checking the comb for live lice. If live lice are found, there are two main approaches. The first is a physical insecticide lotion, such as one based on dimeticone, which works by coating and physically disabling the lice rather than poisoning them. The second is wet-combing, a careful, repeated combing-out of lice and eggs from wet, conditioned hair over a set series of sessions. Whichever method is chosen, treatment is repeated after about a week. This second round matters because no method reliably kills all the eggs, so repeating catches lice that have newly hatched before they can lay eggs of their own. Alongside treating the affected person, it is sensible to check the heads of close household contacts and treat only those who are also found to have live lice. There is no need to treat people without live lice, wash bedding excessively, or keep children off school.
For this condition, these medicines
Medicine classes used for Head lice (nits)
Each links to a full, dose-free guide — what it is, how it works, who can and cannot use it, side effects, interactions and FAQs.
Symptom checker
Symptoms that can point to Head lice (nits)
Head lice (nits) can be one cause of these symptoms. Each guide explains the other possible causes and the red-flag warning signs that mean you should get urgent help:
Beyond medication
Lifestyle and self-care
Checking heads regularly by detection combing on wet, conditioned hair helps spot lice early; treating only people who have live lice, repeating treatment after about a week, and checking close household contacts (treating only those who also have live lice) are the practical mainstays. There is no need for excessive cleaning, and no reason to keep a child off school — lice are not a sign of poor hygiene and do not spread disease.
When to get help
When to see a doctor
Head lice can almost always be managed at home, but it is worth asking a pharmacist or GP for advice if you are unsure whether what you are seeing is genuinely live lice, if treatment does not seem to be working after you have completed a course and the repeat treatment, or if the scalp becomes very sore, weepy or shows signs of skin infection from scratching. A pharmacist can confirm the right product and explain how and when to repeat it. Seek advice too if lice keep returning despite correct treatment, as this may mean a close contact is still carrying live lice and needs checking and treating, or that the method needs reviewing.
Not sure how urgent it is? It is always OK to call NHS 111 for advice, day or night.
Answers
Head lice (nits): frequently asked questions
What medicines are used for head lice?
There are two main approaches, used only when live lice have actually been found. The first is a physical insecticide lotion, such as one based on dimeticone, which coats and physically disables the lice rather than poisoning them. The second is wet-combing, a careful and repeated combing-out of lice and eggs from wet, conditioned hair. Whichever you choose, the treatment is repeated after about a week, because no method reliably kills all the eggs and the repeat catches lice that have newly hatched. Only people with confirmed live lice should be treated — there is no benefit in treating as a precaution. A pharmacist can advise which option suits you.
Why do I need to repeat head lice treatment after a week?
Repeating treatment after about a week is essential because no treatment, whether a lotion or wet-combing, reliably kills all the eggs. Eggs that survive the first treatment hatch over the following days into new lice. By repeating the treatment after roughly a week, you catch these newly hatched lice before they grow up and start laying eggs of their own, breaking the cycle. Skipping the second round is one of the commonest reasons treatment seems to "fail" when in fact lice have simply hatched and re-established. So always complete both rounds, even if you cannot see any lice after the first.
Should I treat the whole family for head lice?
No — you should only treat people who actually have live lice. The right approach is to check the heads of close household contacts using detection combing on wet, conditioned hair, and then treat only those in whom live lice are found. Treating people who do not have live lice "just in case" is unnecessary, wasteful and not recommended. That said, because lice spread by head-to-head contact within households, checking everyone who lives in the home is sensible so that anyone who is also affected can be treated at the same time, preventing them from passing lice back again.
Are head lice a sign of poor hygiene?
No. Head lice are very common, especially among children, and are spread by direct head-to-head contact rather than by being dirty. They are equally happy on clean and unwashed hair, so catching them says nothing about how clean a person or their home is. They do not spread disease and are a nuisance rather than a danger. There is no need to keep a child off school, and no need for excessive washing of bedding or belongings. The focus should simply be on confirming live lice, treating those affected, repeating after about a week, and checking close contacts.
Sources
Where this is drawn from
- NICE CKS: Head lice.
- British Association of Dermatologists: Head lice.
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