Dimeticone (Hedrin lotion)

How does it work?

Hedrin lotion and Hedrin lotion spray both contain the active ingredient dimeticone, which is a silicone-based substance. It is used to treat head lice infestations.

Hedrin works in a different way to conventional insecticides for head lice. Instead of poisoning the parasites by chemical means, the dimeticone in Hedrin lotion works by physically coating the lice. This stops them moving and feeding and also prevents them from being able to excrete excess water. Both actions kill the lice. Head lice cannot become resistant to the lotion because it works in this physical way.

The lotion doesn't kill the eggs, so treatment should be repeated after seven days to kill any lice that have hatched from eggs since the first application.

If the head lice come back, the treatment can be repeated straight away.

What is it used for?

  • Head lice.

How do I use it?

  • All family members with head lice should be treated on the same day to avoid re-infestation.
  • Hedrin lotion and lotion spray should be applied to dry hair.
  • Apply the chosen product carefully over all the hair (the spray may be easier to apply), then massage it in well from roots to tips until the hair is completely wetted. The amount of product needed depends on the thickness and length of the hair.
  • The best way to apply the lotion, particularly with with long hair, is to make a small parting and apply a few drops of the lotion along the hair, then spread this evenly along the length of the hair. Repeat the process with numerous other small sections until the whole scalp has been covered.
  • The spray should be applied from a distance of about 10cm from the hair. Take care to avoid spraying it on the face and don't breathe in the spray. Make sure enough is applied to soak the scalp and hair, then work it in with the fingers or a comb, spreading it from root to tip.
  • Leave the hair to dry naturally in a warm but well ventilated room (don't use a hairdryer).
  • After 8 hours, or the next day if preferred, wash the hair with normal shampoo, rinse thoroughly and dry. Any nits (empty egg cases) can be removed with the fingers or a fine toothed nit comb.
  • The treatment should be repeated after seven days to kill any lice that have hatched from eggs since the first application.


  • Hedrin lotion and lotion spray are for external use on the hair only.
  • Avoid inhaling the spray.
  • Avoid getting the product in the eyes, or inside the mouth or nose. If you accidentally get it in the eyes, rinse them immediately with plenty of water.
  • Do not use near naked flames or lit objects, such as gas and electric fires. Do not smoke during the treatment. Treated hair can burn readily if ignited.
  • If the product causes a rash or irritation of the skin wash it off straight away with normal shampoo. If irritation persists consult your doctor or pharmacist.

Not to be used in

  • Infants under six months of age, except on medical advice.

This medicine should not be used if you are allergic to one or 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 medicine 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.

  • This lotion is not absorbed through the skin and can be safely used by women who are pregnant or breastfeeding.

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 does not mean that all people using this medicine will experience that or any side effect.

  • Skin irritation.
  • Flaking of the scalp.
  • Itching or irritation around the eyes.

The side effects listed above may not include all of the side effects reported by the medicine'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 ingredient

Hedrin once spray gel and liquid gel, Linicin lotion, Lyclear spray and mousse and NYDA pump spray all contain dimeticone as the main active ingredient.