Head Lice: What to Do When Nothing Seems to Work?

There are four reasons why treatment of head lice can fail.

Cause 1: The Head Lice Treatment Was Not Applied Properly

In this situation, the chemical does not come into contact with the lice long enough at a high enough concentration. This is usually due to not covering all the hairs adequately with the chemical. Cover the hair from roots to ends with the product. One way to make sure that you have covered all the hair is to comb the product in with a normal comb. Check how you are applying the product and read the instructions on the package. If you have done all of this then application is not a problem.

Cause 2: The Lice Are Resistant to the Insecticide Used

Head lice can become resistant to insecticide. Some strains appear to be resistant to at least two insecticides at the same time. You can tell if the head lice are resistant by treating the head adequately as described in Cause 1 and then checking for live lice. Use a fine toothcomb and look for movement. If they are all dead or immobile, the lice are sensitive to the insecticide. If the lice are still active, they are resistant to the insecticide in that product.

KEY POINTS: note the "active ingredient", not the product name. If the lice are resistant, switch to another brand with a different "active ingredient".

Cause 3: A Second Treatment Was Not Used to Kill the Newly Hatched Eggs

No product kills 100% of eggs, even if the strain of lice is sensitive to the active ingredient. Eggs take 7 days to hatch. Therefore, starting from 1 day after treatment to 7 days, nymphs may be hatching. Retreatment at 7 days is a mandatory part of treatment. At this treatment if things are going well, you should expect to find nymphs, but no adults. At 14 days, you should recheck the hair, and retreat a third time if you find nymphs.

Cause 4: Reinfestation Occurs

Reinfestation can complicate treatment of head lice. This happens usually from head-to-head contact with a person who has lice. Reinfestation from the environment is very rare. Reinfestation is hard to detect. Suspect it if you have a sensitive strain as shown by testing as described in Cause 2 and are treating it correctly (Cause 1 and 3), but you unexpectedly find adult lice in the hair. Check the hair daily by using a fine-tooth comb. If the hair is clear one week and lice are present the next, reinfestation is highly likely.

However, don’t blame reinfestation for persistence of head lice until you have ruled out the other causes. If you suspect reinfestation, ask your child with whom she/he has had head-to-head contact, and see if they can be checked. Don’t just concentrate on the classroom; look at head-to-head contact opportunities at play and in the family. Be systematic. Do not expect a cure in less than a week. Keep a balanced view. Head lice infestations are a nuisance but do not spread disease.

Do Not Use Measures That Put Your Child’s Health at Risk

With the growing concerns about resistance of head lice to current treatment with pyrethrin and permethrin as the "active ingredient", many people have turned to alternatives. Some are ineffective or dangerous or may create more emotional harm to the child: 

Hair Removal

Shaving a child's head may be effective in getting rid of the head lice however the child will become the focus of teasing among classmates. Is this treatment worth the negative impact on the child's self-esteem? On the other hand, this is historically an effective treatment. Maybe it can be made out to look cool. 

Flammable Chemicals 

Deaths and injuries have occurred when flammable chemicals have been used to treat head lice. 

Dangerous Pesticides

Some people resort to using dangerous pesticides which are not meant to be used on humans. Some examples include veterinary flea preparations, concentrated pesticides and industrial strength diazinon. Their toxic effect on humans may cause death or brain damage.

Suffocating Treatments

The effectiveness of using olive oil or mayonnaise has not been tested. Wrapping a child's head in plastic overnight is creates a suffocation risk. 

Nit Cement Dissolving Agents

Several commercial products have been marketed but have not been proven to be effective. The use of vinegar has been found to cause face and eye burns. 

Household and Environmental Sprays

The head is where lice live and they are very rarely found elsewhere. Environmental sprays tend to be overused and there is no proof that they are safe once inhaled. Just imagine a sleeping child lying face down on a heavily sprayed pillow for a 10-hour sleep. It is recommended, instead, to wash pillowcases and vacuum. 

Nature’s Source offers the full line of Thursday Plantation product a unique range of hair care products that contain 100% pure Australian Tea Tree Oil to clean hair, improve your scalp’s health and control head lice. Suitable for all hair types, especially sensitive scalps. Free from sodium lauryl sulphate (SLS), sodium lauryl ether sulphate (SLES), silicon’s, propylene glycol, synthetic parabens, colours and fragrances 

Thursday Plantation Head Lice Removal Kit with Tea Tree Hair Gel 125g Comb the lice, nits and eggs out of the hair with a permethrin-free lubricating gel

Thursday Plantation Head Lice Removal Kit contains a specially designed stainless-steel comb to remove head lice/nits and a lubricating tea tree hair gel that won’t run into children’s eyes 

• Pesticide free, perfect for safety-conscious parents
• Low para-cymene content to minimize skin irritation
• No mess, no drip gel to avoid run-off into children’s eyes 
• Free from synthetic parabens, propylene glycol, SLS, silicons, synthetic fragrances, synthetic colors, synthetic preservatives and animal derived ingredients 
• Contains 100% pure Australian tea tree oil

Tea Tree Shampoo 200ml

Made with nature’s oils and plant extracts, Thursday Plantation Tea Tree Shampoo gently cleanses the scalp and hair without stripping the natural oils essential to their health. Aloe vera and jojoba combined with lime and lavender oils gently hydrate and condition while chamomilla recutita (matricaria) flower extract help calm and soothe the scalp. 

• Contains 100% pure Australian tea tree oil, an antibacterial ingredient 
• Contains naturally derived ingredients

Tea Tree Conditioner 200ml

Made with natural ingredients, Thursday Plantation Tea Tree Conditioner contains aloe vera, jojoba and olive oil to deeply condition, add body and revitalise hair. 

• Contains naturally derived ingredients 
• Gently detangles and gives lustre back to the hair

Tea Tree Scalp Care Shampoo 250ml

Thursday Plantation Tea Tree Scalp Care Shampoo contains tea tree oil and gentle cleansers to effectively clean and soothe flaky and itchy scalp caused by dandruff. 

• Contains 100% pure Australian tea tree oil 
• Leaves hair soft and manageable 
• Helps prevent dandruff by cleansing and purifying the scalp
• Ideal for dandruff, flaky scalp, build-up on scalp and oily hair