What are Super Lice?

If you’re a parent, you may know how frustrating it can be to deal with head lice. Imagine that frustration magnified because you are struggling to get rid of the little pests only to find out you are dealing with ‘Super Lice’. This article will give you all the information you need to help you feel equipped to eliminate head lice, whether they are ‘super’ or not.

What are ‘Super Lice’?

‘Super lice’ are head lice that have evolved to become resistant to certain insecticide-based ingredients found in traditional head lice treatments used over-the-counter.1,2 However, there are still treatments available over-the-counter which are effective in eliminating ‘super lice’.

What do Super Lice look like?

There may be the assumption that super lice must be supersized, but in fact, super lice look just like normal head lice.3,4  You won’t find a cape, or an ‘S’ on their back, and you will not find any wings either. 

Head lice are tan to greyish in colour.4 When first born, baby head lice are called ‘nymphs’.4 Nymphs are about the size of a pin head and take 7 to 10 days before they mature into an adult louse capable of breeding.4  When fully grown, adult lice are about 3mm long, which is roughly the size of a sesame seed.  Head lice have six legs ending in special hook-like claws for holding onto hair.4

Female head lice are slightly larger than males, and they lay 5-6 eggs (nits) per day each ‘glued’ to a hair shaft near the scalp.5 The eggs are oval shaped, yellow-whitish in colour and will usually be found within 1cm of the scalp. 5 It takes around 7 days for the eggs to hatch where you are left with an empty eggshell still glued to the hair which is called ‘a nit’. 5


How are Super Lice spread?

Without wings, or a cape, super lice cannot fly from host to host.4 Super lice cannot jump from person to person like fleas, and they cannot swim either. 4 The most common way super lice move from host to host is through direct head-to-head contact. 4 It is rare, but possible, for super lice to be spread through the sharing of personal items like hairbrushes, headphones, towels, pillows, hats, etc.6


What are the signs and symptoms of Super Lice?

Super lice do not give hosts a super bite, but the bite of a super louse can leave the host feeling itchy.  In fact, it is hard to tell the difference between normal head lice and super lice by the signs and symptoms.3  As well as the presence of nits and lice, the signs and symptoms which indicate the presence of normal and super head lice are:3,4

  1. Itching
  2. Moving/ tickly sensation on the scalp
  3. Red bumps or sores on the scalp, neck and shoulders – caused by an over-reaction of the body to the lice bites
  4. Excoriated/ damaged skin on the scalp and neck from excessive scratching
  5. Difficulty sleeping
  6. Irritability

One thing to mindful of is the possibility that some people could be ‘asymptomatic’, which means the person fails to show the noticeable symptoms associated with head lice.5  Some people do not experience any itching as this is caused by an allergic reaction to the head lice bite, and some people are simply not allergic. This means they show no symptoms. 5


How are super lice diagnosed?

The only way to know you are dealing with a super louse than a normal head louse is when your over-the-counter insecticide treatment fails despite following the instructions to the letter.3

It is not enough to diagnose head lice with the presence of nits or itching.4  To diagnose an active head lice infestation you need to find a live louse, which is usually done via a method called detection combing. 4   It can be unnerving for many parents to find these little bugs in your child’s hair without then worrying if you are dealing with a super resistant bug.  You don’t have to worry.  There are still many treatments available over the counter that can eliminate both normal and super lice.


Why do some head lice treatments fail?

The following are common reasons why head lice treatments may fail:6


Some people are known to experience a ‘psychosomatic itch’ when they hear the someone mention head lice – this is the presence of the itch symptom but with no physical cause (i.e. no head lice present).  Remember, not everyone itches when they get head lice, and itching could also be a sign of other conditions like dandruff, eczema, or psoriasis.  Did you know, it is also possible to experience the itch symptom after successful eradication of head lice? This is because the allergic reaction can take weeks to develop6

Too much conditioner6

Conditioner is liberally applied when wet combing to help reduce the movement of the lice and make it easier for the comb to pass through the hair.  However, if you want to use a treatment after wet combing and you do not rinse the conditioner thoroughly from the hair, it can hinder the action of the head lice treatment.

Lack of coverage6

If you have thick, long, or curly hair, you may find that you need more than one bottle of head lice treatment to effectively cover all your hair to ensure successful treatment.  If you do not cover your hair liberally from root to tip then there is the potential that the treatment may fail.

Lack of time6

Different head lice treatments recommend different leave on times depending on how they work.  Not leaving the product on for long enough is a common reason head lice treatment fails.  It is important to follow the instructions to the letter to ensure successful eradication of head lice and their eggs.

Poor timing6

Some treatments require more than one application to be successful as they only kill the lice and not the eggs.  It is important to time the applications correctly, as making a second application too soon after the first treatment means you will still have some eggs unhatched that will survive the treatment. On the other hand, making a second application too late could result in new eggs deposited that will be resistant to treatment.  Make sure you read the instructions to tell you how many applications and when to apply them.


This is not exactly a treatment failure, but it feels like one because the lice are back.  In this case, the person was treated successfully, and the lice were eliminated, but then the person becomes infested again by lice spread from another infested person.  This is why it is important to check the entire household and treat everyone infested on the same day.


You are dealing with super lice who have developed an immunity or resistance to common insecticide treatments.  Check with your pharmacist that you are not choosing products which have ingredients which super lice are resistant to.


What treatments are Super Lice resistant to?

Traditional treatments used to eliminate head lice and their eggs were insecticides containing ingredients like Permethrin and Malathion.2,4  The insecticides were used to poison the lice by chemical means which resulted in paralysis and death of lice, but have no effect on their eggs, which is why 2 applications 1 week apart were recommended to kill newly hatched lice.2,3 

Super lice have evolved to be resistant to products that contain Permethrin and Malathion and for that reason they are no longer recommended.2,4,7


How do you get rid of Super Lice?

Be assured that there are effective treatments available over-the-counter that can help you get rid of super lice.  There are two main treatment options available to help eliminate super lice:4

  • Wet combing4 – the methodical combing of hair using a fine-toothed ‘nit comb’. This option is relatively inexpensive but requires more time investment as the wet combing needs to be done on days 1, 5, 9, 13 and 17 following discovery of the infestation to be absolutely sure all head lice and eggs have been removed.  The longer and thicker the hair, the more time consuming it can be.
  • Physical insecticides4 – these are different from traditional chemical insecticides because they work by killing the lice through a physical mode of action such as dehydration or suffocation. This means they are less likely to have issues with resistance.  Physical insecticides contain ingredients like Dimeticone, Mineral Oils, Isopropyl Myristate, Isononyl Isononanate, Oxyphthirine, Osmolone. These ingredients are available in different formats to suit your preferences, such as shampoo, spray, lotion, etc.  It may be tough to remember the ingredient names, but you can ask your pharmacist to recommend a product that doesn’t have issues with resistance.


Can you prevent catching Super Lice?

Head lice, even the super kind, are a normal part of childhood.  It is very difficult to prevent catching these pesky critters as it is difficult to ask children to avoid any contact with the other children in their social circles.  However, there are some tips that can help reduce the risk of catching and spreading head lice, such as:3

  1. Check your child once a week for head lice to help catch them as early as possible and reduce the spread
  2. Avoid sharing personal items such as, hairbrushes, combs, headphones, hats, scarves, etc.
  3. Avoid activities where there is a possibility of head-to-head contact

There are some sprays that claim to act as head lice repellents available over-the-counter, if you are looking for some extra help keeping those lice at bay.

Remember, there is no need to worry about your kids catching super lice because there are effective treatments that can help you get rid of these pesky parasites.


  1. American Academy of Pediatrics (2016) Report on lice retrieved from https://www.aappublications.org/news/2016/04/11/Lice041116
  2. Expansion of the Knockdown Resistance Frequency Map for Human Head Lice. Kyle et al. Journal of Medical Entomology, Volume 53, Issue 3, May 2016, Pages 653–659. Available at: https://academic.oup.com/jme/article/53/3/653/2222496
  3. https://www.healthline.com/health/super-lice
  4. NICE Clinical Knowledge Summary on Head Lice. Available at: https://cks.nice.org.uk/topics/head-lice/
  5. Carl Cummings, Jane C Finlay, Noni E MacDonald, Head lice infestations: A clinical update, Paediatrics & Child Health, Volume 23, Issue 1, February 2018, Pages e18–e24, https://doi.org/10.1093/pch/pxx165
  6. https://www.cdc.gov/parasites/lice/head/gen_info/faqs_treat.html
  7. https://www.pharmaceutical-journal.com/learning/learning-article/head-lice-resistance-and-treatment-options/20201639.article?MsgId=1010496