Head lice can sometimes be difficult to treat due to a high re-infestation rate and their ability to develop resistance to traditional insecticides contained in some medications.
It is thought that head lice will not develop immunity to the newer silicone- and oil-based preparations because they have a physical rather than a chemical action on lice.
After a head lice infestation has been confirmed, you can treat the lice at home by wet comb using a head lice comb or medicated lotions (see below).
However, neither treatment method will protect against re-infestation if head-to-head contact is made with someone with head lice during the treatment period.
Wet-combing method
The wet-combing method involves removing the head lice by systematically combing the hair using a special fine-toothed comb with a spacing of less than 0.3mm. Your pharmacist can advise you on which combs are suitable.
No medicated products are necessary for wet combing. This can be beneficial because head lice are becoming more resistant to the insecticides that are commonly used to remove them.
However, the success of the wet-combing method depends on adopting a painstaking approach that involves regular and thorough combing.
The wet-combing method is described below.
- Wash the hair using ordinary shampoo and apply ample conditioner, before using a wide-toothed comb to straighten and untangle the hair.
- Once the comb moves freely through the hair without dragging, switch to the louse detection comb. Make sure that the teeth of the comb slot into the hair at the roots with the bevel-edge of the teeth lightly touching the scalp.
- Draw the comb down to the ends of the hair with every stroke and check the comb for lice.
- Remove lice by wiping or rinsing the comb.
- Work methodically through the hair section by section so that the whole head of hair is combed through.
- Rinse out the conditioner and repeat the combing procedure in the wet hair.
- Repeat the procedure on day five, nine and 13 in order to clear the young lice as they hatch, before they have time to reach maturity.
The time that it will take to comb your child’s hair will depend on the type of hair that they have and its length. For example, short, straight hair can be quickly prepared and can be fine-toothed combed in a few minutes, whereas longer, curlier hair will take longer to comb.
Medicated lotion or spray
Medicated lotion or spray is an alternative method for treating head lice. However, no medicated treatment is 100% effective. Your pharmacist will be able to recommend an over-the-counter lotion or spray.
Medicated treatments should only be used if a living (moving) head louse is found. Crème rinses and shampoos are not thought to be effective and are therefore not recommended.
Make sure that you have enough lotion to treat everyone in your family who is affected by head lice. Use enough to coat the scalp and the length of the hair during each application.
Follow the instructions that come with the medicated lotion or spray when applying it. Depending on the product you are using, the length of time that it needs to be left on the head can vary from 10 minutes to 8 hours.
The normal advice is to treat once, then repeat after seven days. Some medicated products also supply a comb for removing dead lice and eggs.
Traditional insecticides must not be used more than once a week for three weeks in a row. Some products carry a fire warning.
Some medicated products may be capable of killing eggs as well as lice, although there is no certainty of this. Check for baby lice hatching from eggs three to five days after you use a product, and again 10 to12 days afterwards.
A minimum of two applications of lotion are needed to kill the lice over the hatching period because the lotions do not always kill louse eggs.
If the lice appear to be unaffected by the product (some lice may have developed resistance to a particular insecticide) or if the problem persists, seek advice from your school nurse, health visitor, pharmacist or GP.
Cautions
Always seek advice from a healthcare professional before using medicated head lice lotions on the following groups:
- young babies (under six months old)
- pregnant women
- people with asthma or allergies
Pregnant women are advised to use either wet combing or 4% dimeticone lotion, which is licensed for use in pregnancy and breastfeeding.
Always read the instructions carefully before using medicated head lice lotions.
