How can head lice be treated?

Photo of two girls playing with each other's hair (PantherMedia / Szocs Emese) Head lice don't go away on their own. But there are a number of treatments that are effective at getting rid of them. Many delousing agents don't contain any insecticides.

Head lice often cause itching, but they are not harmful to your health. There are various treatments that are effective against head lice: insecticide-based products and oil-based treatments that suffocate the lice. They differ in terms of how they are used, how they work, and their pros and cons. In Germany, most of these treatments are available from the pharmacy free of charge for children under the age of 12 if they have a prescription. If you aren't sure, you can ask a doctor or pharmacist.

Special lice combs can be used to check whether there are still any lice or nits (lice eggs) in the hair after the treatment. The teeth on a lice comb are less than 0.3 millimeters apart, to catch as many lice as possible. You can also use special nit combs to remove the nits. Nit combs are even finer than lice combs.


Illustration: The life cycle of head liceThe life cycle of head lice

How do you comb lice out of hair?

The best way to comb out lice is as follows:

  • First wet the hair or wash it. To avoid pulling the hair while combing it, you can also use conditioner.
  • Start combing right at the roots of the hair and then carefully pull the comb all the way through to the ends, strand by strand.
  • Wipe the comb on a paper towel or cloth after each strand so it's easier to see any lice.

Head lice don't usually survive being combed out. But to make sure, you can clean the comb in 60-degree (Celsius) water after combing.

Combing out allows you to check for lice and can help get rid of some of the lice, but it's not a sure way to remove all of them.

Insecticide-based treatments

Insecticides have been effectively used to treat head lice for decades. But because they have been used so much, lice have become resistant to them in some European countries. More recent studies have shown that insecticides are now far less effective in France, Great Britain, Denmark and the Czech Republic. There is no research on whether resistance has developed in Germany, too.

The following treatments are considered to be effective and are available on prescription in Germany:

  • Allethrin (trade name: Jacutin Pedicul Spray)
  • Permethrin (trade name: e.g. InfectoPedicul, Ambush, Nix)
  • Pyrethrins (trade name: e.g. Goldgeist, R&C Shampoo)

Each of these products is applied differently, so it's important to read the package insert.

Silicone-based treatments (dimeticone or dimethicone)

Many parents would prefer to treat the lice without the use of insecticides. This fact, combined with increasing resistance, have led to the development of products that work without any poisons. Most of these products contain dimeticone, a silicone oil. Dimeticone is also found in many cosmetics and used in food production.

Products containing dimeticone kill head lice and their eggs by coating them in a thick layer of oil that suffocates them. The advantage of these products is that the lice can't become resistant to them, and that they are not toxic.

Several studies have tested lice treatments containing dimeticone. They show that more than 70 out of 100 children no longer have head lice after the treatment. There is no research comparing the different products to find out which is the most effective one.

Several dimeticone products are available in Germany, most of which can be prescribed by a doctor and are considered to be effective:

  • EtoPril
  • NYDA
  • Dimet 20
  • Hedrin Once
  • Jacutin Pedicul Fluid

Mosquito Med 10 can also be prescribed. It is made out of thick paraffin instead of silicone oil.

These products differ in terms of the active ingredients in them and the total time they need to stay on. Some of them need to stay on overnight, while others just need to be put on for ten minutes.

Plant-based treatments and home remedies

Plant-based products contain plant oils. The different products work in different ways. Some aim to suffocate the lice, others act like a kind of neurotoxin (nerve poison). Only one of the plant-based products available in Germany has been tested in studies: a spray made from coconut oil, anise oil and ylang ylang oil (trade name: Paranix), which can also be prescribed. Products made of mineral oil or neem oil are available too.

Because there is not enough research on these plant-based treatments, it's not possible to say anything about their effectiveness or possible side effects. The same is true for home remedies like vinegar, cooking oil or mayonnaise.

What are the side effects?

All head lice products can irritate the skin or cause itching for a while. Particularly products containing alcohol can cause a burning sensation. One disadvantage of sprays is that they may cause an allergic reaction if inhaled. If a child has asthma or another respiratory disease, it's a good idea to use a liquid product that can be put on with a comb, for instance.

What do you need to consider when using delousing agents?

Regardless of which product you choose, it's important to follow the instructions in the package insert so that the product can work. Some treatments aren’t recommended for very young children or pregnant women. You can ask a doctor if you’re not sure.

Most of the treatments need to be applied again after 7 to 10 days because the lice eggs (nits) can survive the treatment. The second treatment ensures that lice that hatch during the week after the first treatment are killed too.

For the treatment to be able to work, it's important to

  • apply enough of the product to the scalp and hair,
  • spread it evenly,
  • leave it on long enough, and
  • use it on dry hair (wet hair can dilute the active ingredient).

The treatment is very likely to kill the lice. But it's still important to use a lice or nit comb every three days for about two weeks after the treatment, to check whether all the lice are really gone. Some children may need a second treatment, possibly with a different product.

Because some products easily catch fire, the hair must be kept away from candles and other flames while using them. Head lice products should be kept away from your eyes, nose and mouth. If there is contact, it's best to rinse them out with water right away.

When can children return to school or day care?

According to German law, children who have head lice can only return to kindergarten, day care or school after they've had an officially recognized effective treatment. You only need to use it once at first. In other words, you don't need to wait a week until the second treatment is complete. Effective treatments include the insecticides and silicone-based products described above. A doctor or pharmacist can also advise you. Most institutions only ask for an oral or written statement from parents confirming that their child has been treated. Some would like to see a note from the doctor, though.