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Derbac M Liquid - 50ml

Based on 4 reviews
Derbac M
Out of stock
Checked for Accuracy by James O'Loan . CEO & Prescribing Pharmacist . on 20/09/2021

What is Derbac M?

Derbac M is a treatment for head lice and nits which can also be used to treat pubic lice and scabies. It can be used by anyone over the age of 6 months old, making it ideal for all the family. Derbac M does not contain alcohol, which may make it more suitable for those who suffer from asthma or eczema.


What are head lice and nits?

Head lice and their eggs (which are also known as nits) are a common problem that often affects young children. Head lice are tiny insects which cling to the hair, where they lay their eggs. If you have head lice, your scalp may feel itchy and you may be able to feel something moving in your hair. You may also be able to see the lice and nits in your hair.


How does Derbac M treat head lice or nits?

Derbac M uses the active ingredient malathion, which kills head lice, nits, pubic lice and scabies mites. It blocks a natural enzyme in the nit or mite, stopping it from growing and leading to their death.


Can I use this product if I have asthma or eczema?

Derbac M is an alcohol-free formula which makes it ideal for those who suffer from asthma or eczema. The alcohol in other similar treatments can aggravate these conditions, making Derbac M the perfect alternative.


Can I use this product if I’m pregnant or breastfeeding?

You should speak to your doctor or Chemist 4 U pharmacist before using this product if you are pregnant, trying to become pregnant, or breastfeeding. Some medications may not be suitable for you or your baby at this time, and a medical professional may recommend an alternative course of treatment.  


Can I use this product if I’m taking other medication?

If you are using any other medication, including those you obtained without a prescription, you should tell your doctor or Chemist 4 U pharmacist before using this product. Some medications can interact when used together, making them less effective or causing unwanted side effects.


How to use Derbac M to treat head lice

If you are treating head lice, apply enough Derbac M liquid to dry hair that no part of the scalp is left uncovered. Work the liquid into the hair with your fingers, making sure it is spread evenly from root to tip. Leave hair to dry naturally in a warm, well-ventilated room. After 12 hours, shampoo the hair as you usually would, then rinse the hair and comb with a nit comb while wet. This should remove head lice and nits. Repeat treatment after 7 days if necessary.


How to use Derbac M to treat scabies

Apply Derbac M to the entire surface of the skin. If you are an adult, you may not need to apply this product above the neck, but if you are treating a child aged 6 – 24 months then you should apply ta thin film of this liquid to their scalp, face, and ears. Avoid applying this product to the eyes and mouth. Do not wash the liquid off and do not bathe or shower for 24 hours after application. If you have to wash your hands or anywhere else during this time, reapply Derbac M to the area immediately. Repeat the treatment after 7 days. The infestation will be treated by this product, but the scabies rash may persist for up to 7 days.


When should Derbac M not be used?

Derbac M is not suitable for use on children under the age of 6 months. Use Derbac M only on your skin and avoid getting into contact with eyes. Do not use this product on the broken or infected skin. If you have asthma, speak to your doctor or Chemist 4 U pharmacist before using this product. Do not use Derbac M if you are allergic to Malathion or any of the other listed ingredients.


Does this product have side effects?

Like any medication, Derbac M can have side effects, although not everyone will get them. These side effects include:

  • Skin irritation
  • Severe allergic reactions (including difficulty breathing, dizziness, swelling of face, throat and eyes)
  • Chemical burns

If you experience these or any other side effects, stop using Derbac M and speak to your doctor or Chemist 4 U pharmacist immediately. For more information about reporting the side effects of medication, please see the MHRA’s Yellow Card Scheme.


How to store this medication

Store in a cool, dry place that is below 25 degrees C. Protect from light. Store in original packaging and do not use once expiration date printed on label and carton have passed. Keep out of sight and reach of children.


Important Information

This product is a medicine; make sure to speak to your doctor or Chemist 4 U pharmacist before taking this product if you have an underlying medical problem or are taking any other medicine or complementary therapy. If your symptoms get worse or continue after taking this product, contact us or your doctor. For medical services in your area, please refer to

If you are pregnant, trying to become pregnant, or breastfeeding, speak to your doctor or our pharmacist before taking this product. If you suffer from any allergies, ask your doctor or our pharmacist if this medicine is right for you.

Store all medicines out of sight and reach of children.

Please read the included leaflet carefully before using this product.

Please contact your GP if appropriate regarding this product.


Helpful Advice on Medication Restrictions & Addiction

For further information on our medication restrictions policy, please click here.

If you are concerned about an addiction to 'over the counter' medication, we urge you to visit the below links for professional help and advice:

Active Ingredients

  • Malathion


  • Contains Preservatives Methylhyroxybenzoate (218) and Propylhydroxybenzoate (216), Emlsifying Wax, Potassium Citrate Acid, Perfume HT52, Purified Water.
Product Data
Active Ingredient(s)
Chemist 4 U

What are nits and head lice?

Is your child itching away at their head like there’s no tomorrow? Are you tired of telling them to stop scratching their scalp?

Well don’t just assume that they’re being overly dramatic about a little itching, because they could be suffering with head lice!

Yes, those little lice could be making your head a home right now, so let’s take a look at what you can do to evict them before they invite all of their little lousy friends over for a party.

How do I use to treat pubic lice?

Derbac M liquid contains the active ingredient malathion, which is an organophosphorus insecticide that kills parasites such as head lice, pubic lice and scabies mites. This enzyme is essential for the growth and survival of the parasite.

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Shipping Costs

Free UK Delivery on all orders over £30* - Delivery within 3-5 working days.

Standard UK Delivery - £2.95* - Delivery within 3-5 working days.

Express UK Delivery - £4.95** - Delivery within 1-2 working days.

Temperature Controlled Delivery - £8.85 - Delivery within 1-3 working days.

Please Note: These prices are shown as a guide only. All delivery times are approximate but have been obtained in good faith.

*Excluding refrigerated products and treatments which are subject to different postage charges.


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All our items are sent completely discreet for your peace of mind.

This means the packaging is plain, there is no mention of what product is inside your package and there is no mention of Chemist4U either.

We respect that many of our products are of a sensitive nature - this is why we take every step to keep your purchases private.

Returns Information

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