Derbac M


Available strengths:

150 ml

Price £14.99

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Delivery Time


Expected delivery date:

Friday, 8 December 2023

If you order within:


Next Day Delivery

Next Day

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UK Registered Pharmacy

UK Registered

Discreet & Confidential

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  • Overview
  • FAQ
  • Side Effects
  • Patient Information Leaflet
  • Reviews

What is Derbac M

Effective treatment of head lice is necessary to prevent their spread, and there are several products available to eradicate them. One such product is Derbac M Liquid which has an active ingredient proven to kill the lice and their eggs when used as directed. It is also an effective treatment for pubic lice and scabies.

There are certain afflictions which commonly affect children and can be incredibly infectious, spreading to adults easily and one such condition is head lice.

Head lice and their eggs are also known as nits and are most commonly found in young children who acquire them due to them being in close proximity to someone else who has them. They can easily jump from head to head, making the problem very difficult to avoid and easy to spread when mixing with other children. The lice are tiny insects which will cling to the hair and lay their eggs in it and on the scalp. Their presence in your hair usually makes your head feel itchy, and you can often feel them moving in a crawling sensation. They can also be visible to the naked eye.

Other conditions, such as pubic lice and scabies, have similar problems and are equally contagious.

Can I buy Derbac M Liquid online?

Yes. Derbac M Liquid is a medicine, so you should speak to your doctor or pharmacist before using it if you have any underlying health condition. But generally, it is available for purchase online without the need for a prescription or the need to fill out a medical questionnaire. You can buy it from approved pharmacy retailers such as Click Pharmacy.

If you require the product urgently, you can take advantage of the next day delivery service, which will allow you to receive the product to a location of your choosing in a timely manner. Just select this option when you are choosing your preferred delivery as part of the check out process.

If you wish to speak to one of the experts in advance of your purchase, please get in touch with Click Pharmacy. A pharmacist will be happy to help you.

What dose should I choose?

Derbac M Liquid comes in this dose only and should require only a single application in order to eradicate the head lice (or scabies or pubic lice if they are what is being treated). If required, a second dose can be applied 7 days after the first.

The active ingredient is malathion, and it is in this product at a strength of 0.5% w/w.

Derbac M Liquid should always be used as directed – full instructions will be provided within the product packaging.

How should I use Derbac M Liquid?

Derbac M Liquid can be used to treat head lice, pubic lice and scabies. Application of the product varies slightly depending on the infestation being treated:

Derbac M Liquid to treat head lice

Apply the product all over the hair and scalp to ensure no part is uncovered. Hair must be dry before application. To make the process easier (and particularly with long hair), part the hair into small sections and apply the product to the scalp and from the root of the hair right to the ends.

Work the product fully into the scalp and hair to cover it completely.

Leave the hair to dry naturally (do not use a hairdryer) in a warm but well-ventilated room. The next day, or after 12 hours, shampoo the hair as you would normally, rinse it with plenty of clean water and comb it with a fine-toothed comb to remove the dead lice and their eggs.

Derbac M Liquid to treat pubic lice

Apply the product over the entire surface of the skin, paying particular attention to any hairy areas, including beards and moustaches but on no other areas above the neck. Keep the product on for a minimum of one hour but preferably overnight before washing off, as you would normally cleanse yourself.

Derbac M Liquid to treat scabies

Again, apply the product to the entire surface of the skin, including the areas above the neck, scalp, face and ears in children under 2 years old. In older children and adults, this might not be necessary. Always avoid the eyes and mouth.

Leave the Derbac M Liquid in place for 24 hours – do not wash it off. If you do need to wash any body parts within this timeframe, such as the hands, reapply more product immediately after. Once the 24-hour period is over, wash off as normal.

All members of the same family and close contacts should be treated with Derbac M Liquid simultaneously.

How does Derbac M Liquid work?

The active ingredient, Malathion, found in Derbac M Liquid, has been used to treat head lice since the 1960s. It works by attaching itself to a chemical in the louse's nervous system and blocks a natural enzyme in the nit or mite, stopping it from growing and leading to their death because the nervous system collapses.

How effective is Derbac M Liquid?

Derbac M Liquid is exceptionally effective at entirely eradicating head lice with a single treatment thanks to its active ingredient, malathion. This product will ensure all head lice, eggs, pubic lice and scabies mites are killed within 12 hours so that they can be removed from the hair and scalp.

Malathion has been clinically proven as an active ingredient to treat these conditions and is safe enough to use in children as young as 6 months old.

Always follow the instructions for use, which will be provided within the product packaging.

How long do I use Derbac M Liquid for before I notice a difference?

Dependent on the insect being treated, Derbac M Liquid can work in as little as 1 hour. This is the case when it is being used to treat pubic lice, although it would be recommended to leave the product on your skin for up to 12 hours to be sure.

When it is being used to kill head lice and their nits, it can take 12 hours. Once it is applied to the scalp and hair thoroughly and allowed to dry naturally, all the lice and their eggs should be killed, meaning they can be safely washed and combed away. If the infestation is not fully cleared after this application, it can be used again 7 days later to remove the remaining few.

When using Derbac M Liquid to treat scabies, the product should be applied to the body for a minimum of 24 hours. Again, this single dose should be enough to kill all the insects and remove the infestation entirely.

What are the side effects of Derbac M Liquid?

As with any medicated skin treatment, there can be certain cases of side effects, and these are often as a result of an allergy or hypersensitivity to one of the ingredients. Although they are rare, they include:

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

If any such side effects occur, discontinue use of the product immediately, wash it off the skin and contact your doctor or healthcare professional.

Side effects can also occur if the product is misused, for example, if it gets into the eyes or is ingested, so always use as directed.

If you are pregnant or breastfeeding, speak to your doctor before use.

This product does not contain alcohol and is, therefore, suitable for use by asthmatics and those with sensitive skin.

If you wish to speak to any of the experts at Click Pharmacy in advance of purchase to discuss this product, any type of lice infestation or any potential side effects of Derbac M Liquid, please get in touch.

When shouldn't I use Derbac M Liquid?

Derbac M Liquid is suitable for use on all children over the age of 6 months old and adults. Seek medical advice for the treatment of lice and scabies for children under 6 months.

Do not use if you are allergic to the ingredients which are:

  • Malathion 0.5% w/w
  • Methyl Hydroxybenzoate
  • Propyl Hydroxybenzoate
  • Lanette Wax SX
  • Potassium Citrate
  • Citric Acid
  • Perfume HT 52
  • Water

Speak to your doctor or healthcare professional before use if you are pregnant or breastfeeding.

Avoid contact with the eyes and mucous membranes and flush out with water if contact occurs.

If the product is ingested, a doctor or casualty department should be contacted immediately.

What is the difference between Derbac M Liquid and Lyclear Treatment Shampoo / Nitty Gritty Complete Nit Kit?

Lyclear Treatment Shampoo is a fast working solution that can be incorporated into a normal bath-time routine that is very gentle on the skin. You must first remove as many of the lice and eggs as possible using the comb provided before washing the hair in the treatment shampoo. It must be left on for 15 minutes. This product can only be used in children over the age of 2 and is not suitable for pubic lice or scabies.

Nitty Gritty Complete Nit Kit includes a solution to kill the nits and eggs, a comb to ensure they are fully removed from the hair and a spray to discourage any more from getting into the hair.

What is Derbac M Liquid used for?

Derbac M Liquid is a liquid medicine used for the treatment of head lice, crab lice and scabies.

How should I store Derbac M Liquid?

You should store Derbac M Liquid in a cool dry place, out of reach from children and at room temperature. This product should not be exposed to extreme temperatures or direct sunlight.

Do I need to use a nit com after using Derbac M Liquid?

Once you have washed Derbac M Liquid out of your hair you should use a nit comb and comb through your wet hair. This will ensure any dead lices are removed from your scalp.

After using Derbac M Liquid you are unlikely to experience any side effects. This is because Derbac M Liquid does not interfere with anything else. If you experience any of the following:

  • Irritation
  • Severe itching
  • Redness
  • Swelling
  • Difficulty breathing

You may be experiencing an allergic reaction. In this case you should stop using Derbac M Liquid immediately and seek medical advice as soon as possible.

Please read all the patient information that will be included within your product packaging before use.  The patient information leaflet can be found here.

Authored by

Last reviewed 11 April 2023

Superintendent Pharmacist GPhC No.2220953

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