The life cycle of a head louse
A female head louse lays eggs and cements them to a person's hair, often close to the roots, where they are kept warm by the scalp. These eggs are pinhead-sized, making them difficult to see. After seven to 10 days, the lice hatch, but their empty eggshells remain glued in place. These are known as 'nits' and are white in colour.
Nits become more noticeable as the hair grows and they are carried away from the scalp. Head lice feed by biting the scalp and feeding on blood.
They take between six and 10 days to become fully grown. Once mature, a head louse is able to crawl to a different host. A female louse may begin laying eggs as few as seven days after hatching.
Reflective exercise
Six-year-old Zoe comes to the pharmacy with her dad. He tells you that Zoe has developed an itchy rash on the back of her neck and asks if you can recommend a cream. He thinks Zoe may be allergic to the new shampoo she's using, although she's not complaining of having an itchy head. He mentions that her brother had head lice a month ago, but that's all cleared up now.
What would you recommend?
Zoe may have caught a head lice infection from her brother and could now be suffering from a rash on her neck due to a reaction to lice droppings. Refer Zoe to the pharmacist and explain to them that Zoe's brother had head lice recently.
What if:
The pharmacist recommends that you supply a soothing cream to reduce the skin irritation on Zoe's neck. Zoe's dad should also check her head thoroughly for signs of live lice. The pharmacist is needed urgently elsewhere and asks you to provide the necessary advice and treatment options. Zoe's dad is also interested in hearing about prevention treatments for head lice.
What would you recommend?
Suggest they try an antihistamine-containing cream to see if that's effective at soothing the irritation and minimising the rash. Remember, creams containing corticosteroids are not generally suitable for children (especially those under 10 years of age). Explain to Zoe's dad that head lice treatments should only be applied if a live louse is detected in the hair. The easiest way to determine this is to regularly, and methodically, carry out wet combing using a detection comb.
What if:
Zoe and her dad return to the pharmacy two weeks later after finding several lice close to her scalp. He is concerned that his son's head lice may have returned and also that his pregnant wife may have caught the infection. Both children have asthma. Ideally, he wants only one product to treat the whole family.
What would you recommend?
All members of the household should be checked thoroughly for signs of head lice. However, treatments should only be applied if a live louse is found. Show Zoe's dad the range of products that are suitable for use during pregnancy and for asthmatics. Dimeticone lotion or spray is likely to be the most effective, although a water-based malathion treatment would also be suitable. Zoe's dad opts for the dimeticone lotion as they have used it before and found it easy and effective. Remind him that it needs to be left on the hair for eight hours, or overnight, before being washed out using normal shampoo. Everyone in the family should be treated as soon as head lice are confirmed and again seven days later. Detection combing should be carried out two to three days after completing the treatment and again seven days later to ensure the treatment has been effective.