Signs and Symptoms of Head Lice

The thought that you or your child may have head lice can be unsettling. The slightest hint of itching of scratching may leave you suspecting a possible infestation. However, you will soon discover that itching is not always the most reliable way to know if there is head lice present. So, what other signs and symptoms will let you know you have head lice?

Common signs and symptoms of head lice

The most common symptom associated with head lice is itching.3 Even the mere thought of head lice can have people scratching their heads. However, itching is not always the most reliable symptom for knowing you have head lice; this is because the itching is caused by an allergic reaction to the saliva of head lice.2 It can take a few weeks after catching head lice for the first time for the itching to start.2 Some people may never itch because they do not experience an allergy to the head lice saliva.2

There are other signs and symptoms that indicate a possible head lice infestation:

A tickly feeling or moving sensation on the scalp – this is thought to be caused by the movement of the head lice around the scalp.4

Peppery pillow – a pepper like dust may be found on pillows or the scalp; the peppering is caused by louse droppings. Small red bumps or sores – some people may experience mild annoyance from scratching, while others may get a troublesome rash. This rash will likely be found around the scalp, neck and/ or shoulders.1

Oozing crusty sores – Excessive scratching can lead to a bacterial infection which causes oozing, crusty sores to develop.  Watch for swollen lymph nodes (glands) on the back or front of the neck and fever which may indicate a bacterial infection, this can be treated with a course of antibiotics.1

Difficulty sleeping – if the person is plagued by scratching sleep is likely to be impacted.1

Irritability – if sleep is affected by intense itching and scratching then the person is likely to feel irritable and moody. 1

Anxiety – some people feel very anxious or stressed due to the stigma associated with head lice.1

Be mindful that some people may not experience any symptoms at all, this is why the only sure way to know you have head lice is to find a living moving louse.2

How to spot head lice

Head lice can be difficult to spot given that adult head lice are about the size of a sesame seed and baby lice (nymphs) the size of a pin head.1 However, there are tips and tools that may help you detect and eliminate these little critters:

Where to look

looking for head lice can be like looking for a needle in a haystack, particularly if you have thick hair.  However, it can help to know head lice hotspots (their favourite hiding spots) which are the nape of the neck, temples, behind the ears and crown of the head.5 This is where they like to lay their eggs, so it is a good place to start looking for both lice and nits (eggs).5

What do head lice and nits look like?

Adult lice – wingless, 6-legged insects that are tan to greyish-white in colour and about the size of a sesame seed when fully grown.1

Nymph – a newly hatch head louse look the same as an adult louse, except it is considerably smaller as it is about the size of a pin head.1

Head lice eggs (nits) – usually found in head lice hotspots and can sometimes be mistaken for dandruff as they are oval shaped, translucent. They are usually laid within 1 cm of the scalp and will hatch within 7 to 10 days.1

Tools for finding head lice: Nits or lice eggs

Detection comb – a plastic or metal fine-toothed comb sometimes called a ‘nit comb’. With a stroke of this comb it can help you remove both head lice and their eggs.6

Hair conditioner – head lice can move fast around the scalp, however using liberal amounts of hair conditioner can help slow head lice down making them easier to find.6

Tissues – if using wet detection combing you may need tissues to capture the excess conditioner and trapped head lice and eggs after every stroke6

Choosing a detection technique:

Dry detection is quicker than wet detection.  All you need for dry detection is a brush for detangling the hair then a fine-tooth comb for removing any head lice or nits that are found.6

Wet detection may take longer than dry detection, but it is much more thorough and is also considered an effective treatment option for eliminating head lice and nits. You will need a hairbrush, fine-tooth comb, conditioner, tissues, and plenty of time for this technique.6

Who gets head lice?

Head lice can affect anyone of any age.1 However, it is most common in children aged 4-11 years (the peak age for catching head lice is 7-8 years old).1 Head lice have been found to be more common in the following people:1

  • - Girls more commonly have head lice than boys
  • - Children with long hair
  • - Children with more siblings
  • - Families of lower socio-economic status


Head lice are not a sign of dirty hair, as head lice have no preference for clean or dirty hair.1 The likelihood of catching head lice is more likely when there is a ‘clustering’ or gathering of people which increases the chance of head to head contact.1

How do you catch head lice?

Contrary to some myths, head lice cannot jump or fly.1 The primary way of spreading head lice is direct head-to-head contact with another person.1 This can be done by:

  • - hugging or nuzzling someone7
  • - sleeping next to someone, with their head or hair in direct contact7
  • - taking selfies - a study of more than 200 youngsters found those owning a smartphone were more than twice as likely to be infested with lice8


As head lice cannot survive more than 24 to 48 hours without a host, so they are less likely to spread through contact inanimate objects. However, be mindful that there is a small risk of transmission when:

  • - sharing brushes or combs, especially immediately after someone with lice uses them7
  • - sharing hats or scarves, especially if they are passed back and forth quickly since lice die quickly when not on a human head7
  • - sharing towels immediately after someone else has towel dried their hair7

Can head lice be prevented?

It can be very difficult to prevent the spread of head lice, particularly among young children in the community and school. The risk of catching head lice could be lowered if:

  • - children avoid head-to-head contact with friends and classmates during play and other activities
  • - children avoid sharing personal belongings such as hats, scarves, coats, combs, brushes, hair accessories and headphones
  • - children avoid shared spaces where hats and clothing from more than one student are hung on a common hook or kept in a locker
  • - you plait long hair or tie back long hair
  • - people avoid taking selfies with others where there is the chance of close contact between heads
  • - parents refrain from close head-to-head contact with their children – such as hugging or sleeping in the same bed


If you consider the likelihood of the children or parents being able to avoid or limit these behaviours, you can now see why the transmission of head lice is hard to prevent.

There are some products available over the counter in pharmacy that claim to ‘repel’ head lice. Some contain plant oils such as tea tree, anise, ylang-ylang, eucalyptus, and lemongrass; others may contain insect repellent ingredients like IR3535 which have been previously used to repel insects like mosquitoes.

Since the prevention of head lice can be difficult, it is recommended that you regularly inspect your child’s hair for head lice at least once a week. If you do find an infestation, then there are simple steps you can take to deal with head lice.

Head lice treatments

Your do not need to see your GP about head lice as treatments to get rid of these pesky parasites are widely available to buy from pharmacies, supermarkets and online.

The main type of treatments available are:

  • Insecticides – these kill head lice by chemical means, however there is some concern about resistance to this type of head lice treatment.6
  • Non-insecticides – these kill head lice and their eggs by physical means such as suffocation or dehydration.  There is less chance of resistance to these types of products. If you suspect they have no worked, it is more likely that an insufficient amount of the product was used or it was not left on long enough.6
  • Wet detection combing – this is an inexpensive way of eliminating head lice and nits, but it is much more time consuming. 6


If you need more advice about how to recognise the signs and symptoms of head lice or find an appropriate treatment, your local pharmacy team can help you. They are the most accessible healthcare professional you can talk to where no appointment is necessary.