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New best practice guidelines for managing head lice

Christine Brown
Independent Nurse Consultant
Retired (formerly employed by the Medical Entomology Centre)

Approximately one in 10 primary school children have head lice at any one time; yet, families are poorly informed about this common pest.1 The public still perceives school nurses as being at the forefront of the fight against head lice. Forty-six per cent of parents with children at primary school do not understand the need to check regularly for head lice, while a third do not know what to look for, and one in four think schools check for nits on their behalf.2

Despite national guidelines highlighting school checking as an ineffective approach, 85% of parents would like to see a return of the "nit nurse".3 Not only do they believe the school nurse would check their child's hair more thoroughly and accurately than they could themselves, but they also believe they are less likely to miss an infestation. Unfortunately, however, this is not so, as the millions of checks carried out during the 20th century failed to eradicate head lice.

Parents are clearly frustrated by head lice, however rather than trying to assign blame, the key to combating head lice is for all parents to check regularly and take swift action should they be found.

Primary responsibility for head lice management and treatment lies with parents; however, it is essential they are given the right support from healthcare professionals to manage the condition effectively.

To provide help to parents, the UK's leading head lice experts and senior representatives from the pharmacy community have come together to agree the golden rules of head lice management with a simple and memorable 'check, treat, complete" slogan to help parents remember how best to manage head lice (see Box 1).

[[Box 1 headlice]]

These best practice guidelines are based on the latest clinical evidence and national guidelines on head lice management.

What are head lice and what should parents check for?
Head lice are small, six-legged wingless insects that live on or close to the scalp, feeding on blood from the scalp. They range in size from a full stop to a sesame seed depending on their age - adult lice are just 3-4 millimetres long. At about 10 days old a female louse will start to lay eggs after being fertilised by a male louse and will lay between 50 and 150 eggs during her lifetime.

Louse eggs are translucent, which makes them hard to spot - each one is laid on an individual hair as close to the scalp as possible making them difficult to remove with a comb. On hatching, a young louse (known as a nymph) is transparent but after its first blood meal it will darken to a greyish brown colour. It is important to note that nits are not the same thing as lice. Nits are the empty eggshells that remain glued to the hair shafts long after the nymphs have emerged.

The impact of head lice
The best known symptom of head lice is itching, which can lead to a loss of sleep and concentration, but the presence of head lice does not always cause people to itch, and it can take up to three months before this symptom develops. Some individuals never experience it.

Untreated, lice can result in loss of self-esteem and confidence, and long-term infestations can have similar symptoms to low-grade flu. Unsupported, the problem causes parents and children a great deal of unwarranted anxiety and distress. However, parents should be advised to try not to make too much of head lice - they are unpleasant but they rarely do any serious harm.

How to check for head lice
A diagnosis of head lice infection cannot be made without the presence of a living, moving louse - no matter how many nits are present, how many reported cases are in school or how bad the itch is.

Checking for head lice shouldn't be considered a big deal; it should be a normal part of a family's personal hygiene routine like brushing teeth or washing hair. Parents should check their children's hair regularly, ideally once a week, including during the school holidays - a good way for parents to remember this is "once a week take a peek".

Having nits doesn't necessarily mean having head lice - when the lice are gone, the nits remain stuck to each hair until they grow out or are combed out.

Some parents seek treatment for perceived cases of head lice infection, which are not current infections but due to factors such as:

  • Itching scalp caused by other skin problems such as eczema or impetigo.
  • Other conditions, such as dandruff, mistaken for head lice.
  • Psychogenic itch on hearing of cases in school.
  • Treated infection but with nits still being found.

It is best to check for head lice using a comb made for the purpose, ideally white so they can be easily seen and with teeth no more than 0.3 mm apart in order to trap head lice - research has found detection combing was nearly four times more effective than visual inspection for finding live lice.4
Good lighting is important and so is comfort; combing hair when wet, or after applying a conditioner may make the process more comfortable, but combing through dry hair can be just as effective.

What are the treatment options for head lice?
There are FOUR principle types of head lice treatment:

  • Non-pesticide treatments.
  • Pesticide treatments.
  • Wet combing with conditioner.
  • Alternative treatments.

The following information is extracted and adapted from the national guidelines within the Stafford Report.

Non-pesticide lotions
These have a physical mode of action. By coating the outside of the lice, their ability to manage water is disrupted causing them to die. Theoretically, this means there is little chance of the lice building up resistance.

There are two main active ingredient options currently in use: dimeticone and isopropyl myristate. Based on clinical evidence, dimeticone is considered the most effective treatment of this nature and, in a recent study, was shown to be significantly more effective at eradicating lice than the pesticide alternative, malathion.5

The current evidence suggests that dimeticone is an effective agent, with lice eradication rates of 97% in a recent study.6 Dimeticone-based treatments, such as market leading brand Hedrin, provide a promising treatment option as its mode of action is one that is likely to avoid resistance issues. In areas or communities where resistance appears to be an issue, dimeticone would appear to be the most favourable treatment option.

Pesticide agents
There is now irrefutable evidence that the head lice population already has, and continues to develop resistance to a number of chemical agents, particularly permethrin.7 In part, this is a result of inappropriate and overuse of these agents over a long period.

Products containing malathion have been used for a number of years and it has a favourable safety record, however the levels of resistance to this agent are high. One recent UK study found that malathion eradicated lice in only 33% of those treated with it.8

Past evidence demonstrates eradication rates of between 19% and 67%.9 However, there is evidence that levels of resistance to this agent are also high. The preparation currently available is not recommended by the British National Formulary for the treatment of head lice.10

Wet combing with conditioner
Parents may wish to use a non-chemical approach, the most established of these is wet combing with conditioner, often known as "BugBusting®".

This is labour intensive and requires a high level of commitment on behalf of the parent or carer and co-operation from the child. It is recommended that, where parents wish to use this technique, the correct equipment, particularly the fine-tooth BugBusting® comb is used.

However, there is evidence of limited effectiveness even when the BugBusting regimen is well adhered to, with eradication rates of between 38% and 57% reported.11,12

Alternative treatments
A number of products based on alternative approaches are currently on the market. Unfortunately many of the alternative products available lack an evidence base or product license on which to assess effectiveness. In addition, the safety of some alternative methods is unknown and there is the risk that safety problems could arise.

On the basis of the evidence available at the time of publication, only two current treatments were recommended by the Stafford Report; dimeticone and malathion.

It is important to complete the head lice checking process once treatment has been applied, and further advice should be sought if the problem won't go away.

Most treatments require them to be repeated seven days after the first application to kill any nymphs which have hatched since the first treatment was applied. The checking process should be repeated a couple of days after treatment to ensure that all the head lice have been killed.

It is possible to rid a community of head lice if there is an appropriate level of information, effort and will.
Schools should have a minimal role to play - but the quality of the information provided to schools by health staff is key to keeping parents confident, unembarrassed and able to combat lice. Bringing back school nurse inspections would not eradicate head lice; however, school nurses usually have responsibility for providing their schools with information.

Parents need to be given clear instructions on how to check for head lice. This should include the need to check regularly, what to look for and how to treat. Myths and misconceptions hamper successful treatment and management of lice.

The frustration of parents will only increase if pesticidal treatments, which clinical tests have shown lice have built resistant to, continue to be recommended.

There will always be families for whom dealing with head lice is beyond their capabilities. Health visitors, school nurses and other community health staff will usually know these families and should perhaps be prepared to give them special help to deal with the problem, perhaps by a home visit to assist with treatment if necessary.  

1. Welsh PHLS (Wales) 2002 - 10%; Burgess and Brown, 1996 (Cambridge, UK) 0.6%-15%
2. Brown C. Getting ahead of head lice: A study into head lice management in the UK, 2009.
3. Consumer survey of 4,000 British adults, conducted by One Poll
4. Balcioglu C, Burgess IF, Limoncu ME, Sahin MT, Ozbel Y, Bilac C et al. Plastic detection comb better than visual inspection for diagnosis of head louse infection. Epidemiology and Infection 2008
5. Burgess I et al. Public Library of Science, November 2007.
6. Kurt O, Balcioglu IC, Burgess IF et al. Treatment of head lice with dimeticone 4% lotion: comparison of two formulations in a randomised controlled trial in rural Turkey. BMC Public Health 2009;9:441.
7. Downs AM. Managing Head Lice in an Era of Increasing Resistance to Insecticides. AM J Clin Dermatol 2004;5(3):169-77.
8. Burgess IF, Lee PN, Matlock G. Randomised, Controlled, Assessor Blind Trial Comparing 4% dimeticone lotion with malathion liquid for Head Louse Infestation. PLosONE 2007;2.
9. Burgess IF, Brunton, ER, Burgess N. Clinical trial showing superiority of a coconut and anise spray over permethrin 0.43% lotion for head louse infestation, European Journal of Pediatrics 2009
10. British Medical Association (BMA), Royal Pharmaceutical Society of Great Britain. British National Formulary 59. London: BMA; 2010.
11. Plastow L, Luthra M, Powell R et al. Head lice infestation: bug busting vs. traditional treatment. Journal of Clinical Nursing 2001;10:775-83.
12. Hill N, Moor G, Cameron MM et al. Single blind, randomised, comparative study of the Bug Buster kit and over the counter pediculicide treatments against head lice in the United Kingdom. BMJ 2005;331:

To see a video with step-by-step instructions
on how to check for head lice visit: