Head lice infestations (pediculosis capitis) are associated with little morbidity but cause strain and distress to parents, carers, and teachers.
Effective pediculicides exist, but head lice in some areas have developed resistance to products with a neurotoxic mode of action.
Products with a physical mode of action are an alternative to neurotoxic treatments; they are nontoxic, and lice are less likely to develop resistance.
Physicians should take an active role in the treatment of head lice infestations by being available to confirm active cases and being knowledgeable about first- and second-line treatment options in their communities.
Knowledge of the life cycle of lice and the mode of transmission emphasise that 'no nit' policies in schools are not effective and should be abandoned.
The head louse (Pediculus humanus capitis) is an obligate ectoparasite that lives on human beings and feeds on human blood. Head lice infestation (pediculosis capitis) mainly affects those who are socially active, particularly young children.
History and exam
Key diagnostic factors
- presence of risk factors
- scalp pruritus
- live nymphal or adult louse
- eggs visible on hair shaft within 1 cm of scalp
Other diagnostic factors
- small red papules under hairline at nape of neck
- erythema with honey-coloured crust on scalp
- aged 3-12 years
- female sex
- close contact with an infested individual
- overcrowding or close living conditions
- low socioeconomic status
- poor hygiene
- contact with contaminated clothes, hair care items, bedding
1st investigations to order
- no tests required
children aged <2 months
children aged ≥2 months and <2 years
children aged ≥2 years and adults
- Seborrhoeic dermatitis
- Other objects in hair
- Clinical report: head lice
- Parasites: lice: head lice treatment
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