Cyclomethicone, isopropyl myristate (Full marks solution and spray)

How does it work?

Full marks solution and solution spray are both medical devices that contain two active ingredients, cyclomethicone and isopropyl myristate. Cyclomethicone is a silicone-based substance. It is used to treat headlice infestations.

Full marks works in a different way to conventional insecticides for headlice. Instead of poisoning the parasites by chemical means, the cyclomethicone and isopropyl myristate in Full marks solution work by dissolving the outer coating of the lice, which dehydrates and kills them.

Headlice cannot become resistant to Full marks solution because it works in this physical way.

Full marks solution should be applied to dry hair. Apply the product carefully over all the hair (the spray solution may be easier and less messy to apply), then massage the solution in well until the hair is completely wetted. The amount of solution needed depends on the thickness and length of the hair. Leave the hair for ten minutes then comb carefully with the lice comb to remove the dead lice and eggs. Wash the hair with a non-conditioning shampoo afterwards.

All family members with headlice should be treated on the same day to avoid re-infestation.

The treatment should be repeated after seven days, as any eggs that survived the first treatment will have hatched by this time.

What is it used for?

  • Headlice.


  • This preparation is for external use on the hair only.
  • Avoid inhaling the solution or spray.
  • Avoid getting the product in the eyes. If you accidentally get it in the eyes, rinse them immediately with plenty of water.
  • If reactions such as coughing, tingling of the skin or itching occur, rinse the solution off with plenty of water. If irritation persists, consult your doctor or pharmacist.

Not to be used in

  • Children under two years of age.

This product should not be used if you are allergic to any of its ingredients. Please inform your doctor or pharmacist if you have previously experienced such an allergy.

If you feel you have experienced an allergic reaction, stop using this product and inform your doctor or pharmacist immediately.

Pregnancy and breastfeeding

Certain medicines should not be used during pregnancy or breastfeeding. However, other medicines may be safely used in pregnancy or breastfeeding providing the benefits to the mother outweigh the risks to the unborn baby. Always inform your doctor if you are pregnant or planning a pregnancy, before using any medicine.

  • The manufacturer of this product does not have information about the use of this product during pregnancy and breastfeeding. The manufacturer states that women who are pregnant or breastfeeding should seek medical advice before using this product.

Label warnings

  • For external use only.

Side effects

Medicines and their possible side effects can affect individual people in different ways. The following are some of the side effects that are known to be associated with this medicine. Just because a side effect is stated here, it does not mean that all people using this medicine will experience that or any side effect.

  • Skin irritation.

The side effects listed above may not include all of the side effects reported by the product's manufacturer.

For more information about any other possible risks associated with this medicine, please read the information provided with the medicine or consult your doctor or pharmacist.

How can this product affect other medicines?

This product does not affect other medicines.

Other medicines containing the same active ingredients

There are currently no other medicines available in the UK that contain a combination of cyclomethicone and isopropyl myristate as the active ingredients.