head lice head pic

Head lice

I don’t really have to tell you what these little critters are. You may remember those dreaded spot checks by mums with their car keys in primary school. Followed by the embarrassment of getting sent home if you were found to be “infected”.

For those with no memory of these pests, other than being called “nit boy”, let me give you the run down. Head lice are tiny wingless parasites, about the size of a sesame seed or strawberry pip, which feed on the blood from your scalp. You catch head lice from close personal contact with someone who has them, which is why it is most common for young children (especially of primary school age) to get them.

Hair cleanliness will not make a difference for your chance of catching lice, its personal contact that really matters. If you work with children, have a little brother or sister, niece or nephew who gets lice it’s very possible they will pass them onto you. If you give them the odd hug or tussle it moves from possible to probable.

There are a number of effective treatments for lice. The most simple is removing the head lice with a comb. You can also get special shampoos containing pesticides that you can get from your pharmacy.

+   Symptoms

Intense Itching (the classic symptom from the TV ads)

  • This is not actually caused by the lice biting your head, the itching is in fact an allergic reaction to the lice’s saliva (yuchhh!)
  • This reaction may also lead to red bumps on the scalp, neck and shoulders
  • You can have lice and not be itchy as the bites may not cause an allergic reaction in all cases
  • You need to be careful if the itching is particularly intense. Scratching your head hard can cause the skin to break and the scratches may get infected (luckily this is the worst possible complication you can get with head lice)

Adult Lice

  • Baby lice are unlikely to be visible as they are very small but adult lice may be seen
  • They are most commonly found behind the ears and at the base of your neck

Lice Eggs (nits)

  • “Nits” is the word we commonly tend to call lice in the UK, but actually is the name of lice eggs. They are very small (about the size of a pin head) and have a white colour
  • Lice lay their eggs close to the scalp in order to keep them warm
  • The eggs cement to the hair and become more visible as the hair grows out

+   Lice Life Cycle

Understanding the life cycle of lice can help you to break the pattern and is an effective way of getting rid of lice. You need to try and de-lice your head in time to prevent the hatched baby lice from being old enough to breed.

  • Adult female lice can lay eggs at about 7 days old
  • The eggs hatch about 7-10 days later
  • In 6 – 10 days the lice are considered fully grown and this is when they start to crawl from head to head
  • Most lice live for about 3 weeks, after they die they often fall off the scalp

+   Treatment

Combing hair (kind of gross but effective)

  • The first step in treatment should be combing through wet hair
  • Wash your hair with normal shampoo and a good amount of shampoo (makes it easier to detangle and comb through the hair)
  • Detangle your hair with a normal hairbrush to make it easy to comb
  • Use a lice comb or fine tooth comb to systematically comb through the hair and remove lice
  • Clean the comb as you find lice and nits (easy to do by rinsing in a bowl of water) to prevent them from being deposited back on the hair strands
  • This should be repeated on day 5, 9 and 13 in order to break the life cycle of the lice and remove baby lice before they can breed

Pesticide Shampoos

  • There are a number of pesticide shampoo treatments you can buy from your local pharmacy, none of which have been proved more effective than others
  • It is worth asking your pharmacist for a recommendation as, in some parts of the UK, some lice have grown immune to the some of the treatments sold
  • You should always follow the recommendations carefully
    • Do not leave the shampoo on too long as it may harm your scalp
    • Avoid your eyes
    • Do not use unless you have confirmed that you have lice (see symptoms above)
    • Do not use as a preventative treatment
    • Don’t cover with a shower cap unless the treatment instructions call for it
    • Those with eczema or asthma may be sensitive to chemical pesticide treatments and wish to try other alternatives first
  • You should repeat the treatment after 7 days in order to get any newly hatched eggs and break the life cycle. Lice eggs are often not killed by pesticide shampoo

Alternative Treatments

  • Tea tree shampoos have been suggested to be effective
  • Some people claim smothering your hair in mayo suffocates the lice killing them. This has not been proved but maybe worth trying?!
  • “Full marks” a non-pesticide based treatment

+   Prevention

Understanding that lice cannot swim, fly or jump may help to keep you calm about possible lice infestations. It’s pretty difficult for you to catch lice from clothing or bedding. Lice can only live for 2 days without blood and only a week without the warmth of a scalp. It is also impossible for lice to live on animals.

  • Avoiding contact with someone who has lice is the best prevention
  • If your lice infestation is particularly bad or if you are a little OCD/freaked out about the whole ordeal
    • Wash your bedding and clothing in water of at least 55 C
    • Drop combs and hairbrushes in really hot water for at least 10 mins (lice can breathe under water for a while)
    • Vacuum your carpets

If you have recently had lice or know someone who has, comb through your hair with a lice comb weekly or monthly, to check they haven’t come back

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