Salicylic Acid Shampoo Ultimate Guide – The 28 Day Results!

  • Medically reviewed by: Debra Rose Wilson, PhD MSN RN IBCLC AHN-BC CHT
  • Written by: William Hartfield
  • Last updated: 04/01/2024

Whether you are suffering from dandruff or sebum buildup, or you are just struggling to keep your scalp’s health in check, you may want to consider using a salicylic acid shampoo.

Salicylic acid has been shown to effectively treat such scalp conditions at the source, and its use is even effective for up to 14 days after use!

This article will offer a deeper look at salicylic acid and its benefits and then provide you with an easy, four-ingredient salicylic acid shampoo that you can make yourself.

First, you will learn what salicylic acid is and the scalp conditions it is commonly used to treat.

Second, we will dig into the research surrounding salicylic acid usage. This will include a look at a study that compared salicylic acid with Nizoral shampoo (with salicylic acid coming out as the clear winner).

Thirdly, you will learn the salicylic acid shampoo recipe recommended to sufferers of scalp buildup.

Finally, the article will show you how to fix the real underlying problem that causes a buildup on your scalp in the first place so you never even have to think about using salicylic acid again.

Sebum buildup on the scalp
A buildup of sebum on the scalp.

What is Salicylic Acid?

A bottle of salicylic acid

Salicylic acid is a phenolic acid, originally sourced from the bark of the white willow, but found naturally in a variety of foods, including blackberries, apricots, walnuts, and peanuts.

This acid contains keratolytic properties, meaning it removes an excess buildup of skin flakes (also called scales) as they develop. This buildup is common in individuals with dandruff and seborrheic dermatitis and is also seen in individuals with scalp psoriasis and eczema.

As such, salicylic acid is a beneficial compound in the treatment of dandruff and other flaking scalp conditions, and should be considered if you are looking for a natural solution to the itching, flaking, and general irritation.

How Does Salicylic Acid Shampoo Work?

Salicylic acid, as described above, is a phenolic acid. More specifically though, it is a beta-hydroxy acid. To understand how salicylic acid works, you first need to understand the acid’s structure.

The chemical structure of salicylic acid.
The chemical structure of salicylic acid.

As a beta hydroxy acid, salicylic acid has a chemical formula that separates the hydroxy group from the acid group with two carbon molecules.

If you are not a scientist, that may not mean much. However, it means a great deal when it comes to how it interacts with your skin.

The two carbon molecules have a big impact on this compound’s effectiveness.

The double separation between the hydroxy group and the acid group makes the compound more oil soluble. This means that it can more easily penetrate the pores than an alpha hydroxy acid (with the hydroxy group and the acid group only separated by one carbon molecule) because it can dissolve – to a certain extent – in oil.

What does this mean for those who suffer from dandruff and other such scalp conditions?

Salicylic acid shampoo can effectively remove scalp flakes while gently cleansing the scalp. This is because it can enter the pores with ease. In addition, this compound can treat clogged hair follicles which is essential if you want a healthy scalp with ample hair growth.

Can Salicylic Acid Combat Hair Loss?

Hair loss has a number of causes – including genetic predisposition, stress, illness, and medications.

While salicylic acid may not combat all types of hair loss, it can certainly contribute to a healthier scalp which is a solid start for anyone looking to grow their hair.

Now, to fully answer the question, here is a look at how salicylic acid works.

Salicylic acid peels are a popular method of use.
Salicylic acid peels are a popular method of use.

Salicylic acid removes the top layer of skin, in addition to the natural buildup of sebum, dead skin cells, and dead hair.

For those who suffer from a scalp condition, such as dandruff or scalp psoriasis, salicylic acid can gently remove the buildup of flakes and provide the hair follicles with a clean environment.

Even for individuals with male-pattern baldness, salicylic acid offers a promising treatment method.

This is because the sebum removed from the scalp contains DHT, the main cause of Androgenetic Alopecia (AGA). With DHT removed from the scalp, there is less risk of hair miniaturization and, as a result, hair loss.

So, can salicylic acid combat hair loss? In some cases, yes.

Salicylic acid is a great way to directly combat hair loss in individuals with dandruff, seborrheic dermatitis, scalp psoriasis, and similar conditions that lead to excess buildup of skin.

In individuals with AGA, it can also be used indirectly, removing DHT buildup from the scalp and preventing it from causing further damage to the hair follicles.

What Does the Research Say About Salicylic Acid?

With salicylic acid treating such a wide array of skin conditions – from acne to dandruff to ringworm and more – it is no wonder that it is the base ingredient for such a large number of cosmetic products.

Fortunately, this compound’s popularity lends itself to some helpful scientific research.

One research study was performed in 2002, and it compared the use of a salicylic acid shampoo with Nizoral shampoo.

Throughout the study, it was clear that both shampoos effectively treated both dandruff and seborrheic dermatitis by reducing flakes and buildup. However, at the end of the study – and even 14 days afterward – only the salicylic acid combination was shown to reduce itching and irritation in patients with seborrheic dermatitis.

Another study, performed by French researchers in 2009, compared the efficacy of salicylic acid in two different combinations.

The first combination was salicylic acid (1.3%) + lipohydroxy acid(0.1%), and the second combination was salicylic acid (3%) + ciclopiroxolamine (1.5%) and menthol.

Both combinations decreased symptoms in individuals with mild to moderate seborrheic dermatitis, including scales, redness, itching, discomfort, and dryness. The combination with lipohydroxy acid (Group I) did show better results, but the differences were not significant.

Scalp symptoms comparison as reports by patients

And as you can see from the graph below group 1 (the dark bars) achieved a higher percentage of improved patients across the 5 main criteria for success:

  1. Dryness
  2. Cutaneous discomfort (unpleasurable sensations in the scalp)
  3. Pruritus (itching)
  4. Erythema (reddening of the skin)
  5. Scale (white buildup)

Are There Side Effects Associated with Salicylic Acid Use?

As with any compound, it is possible to experience an allergic reaction or adverse reaction.

This means it is important to test the product on a small patch of skin before use on your scalp. In addition, you should follow all dilution and dosage recommendations.

If you are pregnant or nursing, consult with your physician prior to use.

The most common side effect is skin irritation (redness, itching, and burning), and the use of salicylic acid should be stopped immediately if this is experienced.

In addition, stop use and seek medical help immediately if you suffer from signs of anaphylaxis (a severe allergic reaction), including hives, difficulty breathing and/or swallowing, swelling of the mouth, tongue, lips, or eyes, or nausea/vomiting.

Brands, Availability, and Cost

There are a variety of over-the-counter shampoos that contain salicylic acid, most of which are targeted at controlling dandruff and other such scalp conditions.

A few popular brands include Neutrogena T/Sal Therapeutic Shampoo, Shea Moisture African Black Soap Deep Cleansing Shampoo, and Avalon Organic Itch & Flake Therapy.

They all utilize salicylic acid as the main ingredient, and they all claim to treat scalp buildup and reduce itching and flakes.

The cost for such shampoos varies by brand and retailer.

Avalon brand as found on Amazon, for example, comes in at $11.22 for 14 fl. oz., while Neutrogena brand can be purchased for $7.14 (4.5 fl. oz.) from the online Neutrogena retailer.

How to Make DIY Salicylic Acid Shampoo

While over-the-counter products can provide you with an easy addition to your hair care routine, they also include various chemicals that can further harm your scalp and lead to hair loss.

Homemade shampoos are easy to make, and the majority of ingredients can be purchased from your grocer or chemist.

Not to mention, when you make your own shampoos, you know exactly what is in your shampoo and, therefore, what is on your scalp and in your body.

White willow bark is a natural source of salicylic acid
White willow bark is a natural source of salicylic acid.

What You Will Need:

  • Distilled water (1 cup)
  • Liquid castile soap (4 tbsp)
  • White willow bark extract (2 tsp)
  • Tea tree oil (10 drops)


Combine the water and liquid castile soap, stirring until you get a soapy solution. Next, add in the white willow bark extract and tea tree oil, and stir until combined.

Mix well before each use.

To apply, pour into palm and massage into wet hair and scalp. Work the solution deep into your scalp, and be sure to pay special attention to the most troublesome areas of your scalp.

Leave in for two to three minutes, and then rinse thoroughly with lukewarm water.

Hair Benefits:

This salicylic acid shampoo is an excellent addition to your hair care routine, treating and preventing the buildup of dead skin, sebum, and harmful chemicals, like DHT.

In this recipe, the white willow bark extract acts as the source of salicylic acid. However, feel free to experiment with other sources (like aspirin) or directly use salicylic acid (3% solution) itself.

Tea tree oil can help reduce fungal infections on the scalp

The tea tree oil adds an additional touch of treatment and prevention, as it is commonly used to treat fungal infections (the source of dandruff and seborrheic dermatitis).

How to Use Salicylic Acid Shampoo Effectively

When it comes to achieving results, utilizing the right products is only half the battle. The other half involves correct use, so let us take a look at how you can use salicylic acid shampoo most effectively.

First, you should use this shampoo just twice per week. Using it too often can strip too much oil from your scalp. Natural oils are healthy, and can actually contribute to healthy hair growth when kept in check. Using it too little, however, can also lead to an unhealthy buildup of sebum, dandruff flakes, and dead skin.

Two times per week seems to be a happy medium, but feel free to experiment and see how using it more or less often affects your scalp and hair.

Second, it is important that you use this shampoo consistently. It is not enough to try the shampoo recipe out once or twice and determine that it is ineffective.

Positive and noticeable changes can take some time to appear. As long as the shampoo is not causing you any discomfort or worsening your symptoms, then you should use this shampoo twice per week for at least six weeks.

This will give you enough time to really determine whether it is the right treatment method for you.

Treating The Real Problem

If you have a buildup of gunk on your scalp, then using a shampoo like salicylic acid may help…

In the short term!

However, you still have not fixed the underlying problem.

Getting rid of one layer of sebum buildup may help your hair, but your body will keep producing the waste products that cause the buildup in the first place.

The way to fix the problem at the root cause is to change what goes into your body.

Ultimately you do not want to be using salicylic acid on your scalp for the rest of your life because it will cause damage by stripping away the natural oils.

Firstly, avoid these foods:

  • Pasteurized dairy
  • Fried foods
  • Highly processed meats

Eat more:

  • Vegetables
  • Raw foods
  • Herbal teas
  • Unprocessed foods


If you are looking for a cheap and effective treatment for hair loss, then look no further than salicylic acid.

This naturally-occurring compound has been scientifically proven to treat dandruff and seborrheic dermatitis, while also removing the excess buildup of oil, dead skin cells, and DHT.

Information contained on this website has not been evaluated by any medical body such as the Food & Drug Administration. All information is for educational purposes only. We do not aim to diagnose, treat, cure or prevent any disease or illness. You must consult a medical professional before acting on any content on this website.