What is Salicylic acid ?

Well, it is considered a type of beta hydroxy acid (BHA). It is a type of organic compound containing and a carboxylic acid group and a alcoholic group at adjacent positions in a benzene ring. It has antifungal, anti-infective, and keratolytic properties.

How is it obtained ?

Firstly it was obtained from the bark of a white willow tree named scientifically as Salix alba. This is where from it got its name. It can also be obtained from wintergreen leaves. Apart from these natural sources, it can also be chemically and biologically synthesized in laboratory from other substances such as phenylalanine, acetylsalicylic acid (also called aspirin).

How does it work ?

As we mentioned earlier, it is famous for its antifungal, anti-infective, and keratolytic properties. We are going to understand what exactly does these words mean.

1. Antifungal- Here it means that the salicylic acid inhibits the growth of fungal agents either by disrupting their lifecycle or by killing them. For example :- In a study it was found that, SA inhibited the growth of blue mold just after 30 minutes of introduction, it did so by disrupting its plasma membrane and hence by causing protein leakage. This is the reason why SA is used along with other substances in antifungal medicines.

2. Anti-infective- By this it means that SA inhibits the growth and the inflammation caused by the bacteria by inhibiting certain mechanisms in bacteria's lifecycle which is necessary for it to proliferate (survive).

3. Keratolytic- SA is a keratolytic agent, what it means is that it softens the skin by exfoliating dead and infected skin, reduces the thickness, increases moisture level.

Foe these reasons this skincare ingredient is very popular in skincare industry.

What are the uses ?

SA has many uses, it has been used to treat skin conditions such as Acne, Dandruff, Psoriasis, Seborrheic dermatitis, Blackheads, Keratosis pilaris, Calluses, Warts, Corns, Plantar warts.

For each of these above-mentioned skin concerns, Different percentage of SA is available in the market. Some are available without prescription while some require prescription.

Up to 2% dosage in topical application products is available in the skincare market.

In skincare concerns such as Blackheads, Acne, Psoriasis, Dandruff, Seborrheic dermatitis, Keratosis pilaris, 2% of SA should be enough.

What percentage you should choose also depends on your skin type. For instance, Oily skin is advised to use 2%, while drier and sensitive skin types are advised to start from lower percentages, and they build up resistance to higher percentages with time. But keep in mind, there is no need to use higher percentages if the lower ones seem to work good on you as higher percentages are also associated with increased risk of skin sensitivity.

Why does SA work at lower pH and not at Higher pH?

The salicylic acid is said to work at a pH range of 3-5. At lower pH it lowers the pH of the outer most part of the skin called stratum corneum, by this it can increase the hydration of keratin (a water-resistant layer), which in turn swells up the corneocytes (cells of stratum corneum). At lower pH it also breaks apart some desmosomes (a part which keep the corneocytes adhesive to one another), thus breaking apart the corneocytes. This way SA removes the outer dead skin layer and unclogs the pores.

At higher pH the SA is rendered ineffective as it cannot perform these above explained functions and at a pH lower than 3, It would be way to acidic and harsh for skin to tolerate.

So, you should look for skincare products which specifies the pH of the product to understand if it would be effective or not. In case of products which do not specifies the pH on the packaging, the only way you can know if it would work is by testing it out on your skin.

Don't worry, even with products specifying the pH, It is not necessary it would work on your skin.

There are many other factors also involved. For example: - the formulation of the product might not suit your skin, but it can suit someone else's skin. That's why it is beneficial to try these products by trying out their testing packaging products.

How to use SA in your skincare ?

If you are just starting out with SA, you can try to incorporate it in your skincare routine in a cleanser formulation. The benefit of using it in this way is that it does not stay on your skin for very long time and with consistent use it is just as effective, thus chances of increasing your skin sensitivity are lower this way. Also, if your skin tolerates it well you can use SA this way daily.

You can use it in toner, serum, cream formulation as well. But try to incorporate it in skincare routine once a week and try to use more often if your skin tolerates it well.

For sensitive skin, you should try lower percentages of SA such as 0.5% and then from there build up your level with time but you do not need do to do so if your skin is working well with lower percentages.

Products that I would recommend

Cleanser formulations:

1. Oil free acne face wash by Neutrogena.

2. Clear Pore normalizing cleanser by paula's choice

3. Pink grapefruit version by neutrogena.

4. COSRX SA exfoliating cleanser

5. Powdered enzyme and SA based cleanser by dermalogica

6. La Roche-Posay Effaclar Medicated Acne Face Wash

Toner Formulations:

1. Paula's choice skin perfecting BHA liquid

2. COSRX BHA powerhead liquid

3. Caudalie vinopure purifying toner

4. La Roche Posay Effaclar Clarifying Solution

5. Benton aloe BHA toner

6. Farmacy Deep Sweep 2% BHA Pore Cleaning Toner with Moringa + Papaya

Serum Formulations:

1. Caudalie Vinopure Blemish Control Salicylic Serum