What is Selsun Shampoo 2.5% and why is it often out of stock in the UK?

Reviewed and fact-checked by Giulia Guerrini, Superintendent Pharmacist. Read our editorial policy to see how we create informative, accurate content.

If you've used Selsun successfully to clear dandruff or dry, scaly scalp conditions, but can't get your hands on a bottle now, you're not alone.

In this article, we'll discuss why you won't be able to buy a bottle of Selsun right now, and two effective alternative treatments you can try:

But first, let's talk about Selsun anti-dandruff shampoo.


What is Selsun Anti-Dandruff Shampoo 2.5%?

Selsun is a brand name for the shampoo which is used to treat dandruff and the skin disorder, seborrheic dermatitis. Some people also use the active ingredient, Selenium Sulphide, to treat tinea versicolor, a condition which causes skin discolouration.

The active ingredient is called selenium sulphide (or Selenium Sulfide) of which there is 2.5% and Selsun anti-dandruff shampoo is currently the only dandruff shampoo (Selsun Shampoo 2.5) which contains 2.5% of the active ingredient. Other alternatives with selenium sulphide generally only contain around 1%.

Selenium is a strong antifungal which is very effective against dandruff and it’s also a cytostatic agent which means it slows down the production of skin cells on the scalp that causes dandruff. You can see why it's in high demand – Selsun really works.


Uses of Selsun Shampoo

Selsun is a medication which should only be used on your skin. Check the instructions in the packaging to make sure you’re aware of how to use it correctly.

As Selsun can damage jewellery, it’s a good idea to take that off before touch it.

You’ll also want to try and avoid this contacting your eyes, or inside your mouth and nose as it can cause some irritation. If it does contact these areas, don’t worry, just flush the area with plenty of water. You can contact our pharmacist if you have any questions.

For treating conditions such as dandruff or scalp dermatitis, make sure you follow either your healthcare professional’s advice or the instructions from the manufacturer.

Make sure your scalp is wet before using Selsun. You can then leave it on your scalp for around 2 or 3 minutes before rinsing it off thoroughly. There are some different types of Selsun which may require repeat application but this should be clear on the instructions.

This is most commonly used 1 or 2 times per week for dandruff and seborrheic dermatitis. Initially, it’s best to use it twice a week for two weeks and then once a week for another two weeks. After that, it’s best just to use it as and when you need to in order to control the condition.

If you’re using Selsun to treat tinea versicolor, apply it to the affected skin and lather in a small amount with water. You’ll want to aim to leave this on your skin for 10 minutes before washing it off with water. If you’re using it for tinea versicolour this can be applied once daily for 7 days. The treatment for tinea versicolour can only be started if you have been told to do so by a healthcare professional such as your pharmacist.

Always make sure to wash your hands and any areas where Selsun was applied thoroughly. Leaving it in contact with your skin risks irritation and won’t help your condition clear up any faster. If your condition worsens, contact your doctor or speak to our pharmacist.


Can I use Selsun Shampoo 2.5 every day?

It’s generally not recommended to use Selsun daily unless you’re using it on a 7-day course to treat tinea versicolor.

Any more frequent usage can lead to side-effects such as a burning sensation if not used in accordance with the time specified. Some people have also seen an increase in hair loss when using the product as well as some hair discolouration. All of this can be avoided if you make sure to use it infrequently and with the guidance of your doctor or pharmacist as well as making sure to completely rinse any area which comes in contact with Selsun. Dryness of the skin can also occur, it’s worth reading all of the side effects on the manufacturer’s instruction leaflet to make sure you’re fully aware.


How long does Selsun take to work on my skin?

If you’re looking to treat dandruff then 5 - 10ml should be massaged into a wet scalp twice a week for two weeks before you see results.

For tinea versicolour, if you apply it daily for 7 days you’ll start to see a noticeable improvement (must be initiated by a healthcare professional).


Where can I buy Selsun Shampoo 2.5?

Previously, you would have been able to buy Selsun Shampoo 2.5% at medino online pharmacy. If you’re looking for where to buy selsun shampoo and you’re finding that it’s out of stock everywhere in the UK, we unfortunately have some bad news – Selsun shampoo has been discontinued (September 2022).

We still have live Selsun shampoo 150ml, 100ml and 50ml pages on medino, where you can sign up for 'back in stock' notifications in case it ever returns, though it seems unlikely. If it ever does, we'll promise to keep the price of Selsun Shampoo 2.5 very competitive for both the 150ml, 100ml and 50ml versions, so you'll be able to pick it back up here. But we do have some alternatives you can buy, which we'll explain in the next section.


Why is Selsun out of stock? Has it been discontinued?

Selsun dandruff shampoo 2.5 has unfortunately now been discontinued (September 2022). Due to its popularity and effectiveness, this is very frustrating for anyone who relies on this effective dandruff shampoo. The reviews showed this product was very effective at treating dandruff and seborrheic dermatitis, and Selsun was the only product available widely with the strength of selenium 2.5% in the market.


What effective alternatives to Selsun shampoo can I buy?

We have two stronger alternative shampoo treatments for dandruff and scaly scalps which are readily available:

  • Dermax Therapeutic Shampoo 250ml. A shampoo treatment for dry, scaly scalp conditions such as seborrhoeic eczema / seborrhoeic dermatitis and pityriasis capitis, also known as severe dandruff. The active ingredient in this product is benzalkonium chloride which loosens scales from the scalp, lifting them from the hair, and acting as a mild antiseptic to help combat yeast which can cause or worsen scalp conditions.
  • Dandrazol Anti-Dandruff Shampoo 100ml. This dandruff shampoo contains ketoconazole, instead of selenium, which is an antifungal which is used to treat dandruff. It also treats inflammation associated with dandruff, relieving itching and redness.
Written by Giulia Guerrini
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