Head lice

Question 1

In who is head lice most and least common?

Answer 1

Most common in children aged 4-11, with girls showing higher incidence.
Rare in adult male due to loss of hair and baldness

Question 2

Does presence of the empty white eggshells mean that head lice is present?

Answer 2

Presence of empty eggshells (white-coloured) attached to the hair shifts is NOT evidence of head lice unless live lice are seen.
Need to explain this to parent that presence of such eggshells do not mean treatment failure, just the egg shells are firmly glued to the hair shafts and not removed by medication and lotions in treatment.
To remove you need to use a fine-toothed comb to remove nits after treatment.

Question 3

Why doe itching occur with head lice?

Answer 3

Itching is not experienced by everyone with head lice. it occurs due to an allergic response to the saliva of the lice, which is injected into the scalp in small amounts each time the lice feed.
Sensitisation does not occur immediately and may take weeks for itching to develop. Thousands of bites are needed for a reaction to develop,
In some people who have had head lice before and have been re-infected, itching may begin early.

Question 4

treatment timescale of head lice

Answer 4

with treatment should resolve within 2 weeks

Question 5

Symptoms of head lice

Answer 5

• ask if patient has had them before or if in family or school- as transmission is head-to-head
• Lice with white eggs. Small, beige, black, greyish or brown coloured specks on pillow and collars.
• Before treating, need to ensure parent had actually seen the lice and eggs or if they’ve already checked by doctor or nurse

Question 6

Referral criteria for head lice

Answer 6

treatment failure

signs of bacterial infection from itching

Question 7

Why is carbaryl a POM?

Answer 7

Carbaryl (head lice treatment) is an POM due to possible carcinogenicity

Question 8

What is the preferred formulation of treatment of head lice?

Answer 8

Lotions
Not so much shampoos and cream rinse as they’ll get diluted and have short contact time and low compliance due to repeated applications

Question 9

What should a parent do if they try one insectide on their child for head lice and it doesn’t work?

Answer 9

If one insectide doesn’t work, try another

Question 10

Lifestyle advice regarding head lice

Answer 10

Removal of stigma of head lice, as clean hair is just as likely to get infected

• wet combing (comb spacing <0.3mm)
• previous treatment failures may be due to too little treatment being used to remove lice and nits properly
• insectides should not be used in prophylaxis of head lice as this can accelerate resistance
• check family members for lice
• contact tracing or track source
• lotion application

Question 11

Lotion application for head lice: directions

Answer 11

50-55mL of lotion is ideal for one application

Use a towel to cover eyes and face

Question 12

How should wet combs be used in head lice treatment?

Answer 12

more reliable detection method than just scalp inspection or combing the hair over a piece of white light coloured paper
the hair should be damp or wet to make combing easier and less painful, as dry hair can cause static and cause lice to repel from the comb
After each stroke, comb should be wiped on a white tissue or cloth
hair should be combed one section at a time
thoroughly check the hair at the nape of the neck and behind the ears- as warm and sheltered area is preferred by lice
Checks need to be carried our regularly, weekly and more if known infection source is the school

Question 13

Hedrin 4% lotion
drug family/type
How does it work to resolve head lice?

Answer 13

Physical insecticide= dimeticone and isopropyl mysristate/cyclomethicone
Dimeticone coats lice and prevents them excreting excess water
Kills lice through physical action

Question 14

Hedrin 4% lotion directions for use

Answer 14

applied to dry hair and scalp, left for 8 hours and then rinsed off.
Second application is needed after 7 days

Detection combing after 4 days and then 8-10 days is recommended
isopropyl myristate/cyclomethicone cream rinse has physical action on lice - apply to dry hair and wash out after 10 minutes

Question 15

Hedrin 4% lotion side effects and counselling

Answer 15

itching or flaky scalp
Irritating if it gets into the eyes
ideal for patients with eczema or asthma sufferers as less irritant on the scalp

Question 16

Lyclear dermal cream 
drug type/class 
How does it work for head lice?

Answer 16

chemical insectide= permethrin and malathion, phenothrin
Kills head lice and their eggs

lotions and liquids are preferred over cream rinse (10mins) and mousse (30mins) due to dilution
residual effect and carbyl

Question 17

Lyclear dermal cream for head lice

Directions

Answer 17

Apply to DRY hair and scalp
Leave in for a minimum of 12 hours (or overnight)
2 treatments should be carried out 7 days apart to avoid re-infection (eggs take 7 days to hatch)
Detection combing after 4 days then 8-10 days is recommended

Question 18

BNF advice on permethrin cream and phenothrin mousse for head lice

Answer 18

Doesnt’ recommend them as short contact time

Question 19

Combing for head lice

Answer 19

wet combing
Fine, metal comb is the best one.
Hair should be shampooed and conditioned/add vegetable oil
The is combed for about 30 minutes every 4 days for minimum of 2 weeks

Question 20

Herbal treatments for head lice

Answer 20

tea tree oil and aromatherapy

Little evidence for effectiveness