What is Salicylic Acid Used For: Properties and Uses

Salicylic acid (2-hydroxybenzoic acid) is a substance with properties to improve acne symptoms, remove warts, reduce calluses and thickened skin caused by aging, as well as to rejuvenate the face.

It is suitable for both young and mature individuals, and its uses are appropriate for treating skin imperfections caused by improper melanin formation. It also helps to restore aged skin tissue by promoting skin regeneration, making it smoother and more even.

It should be noted that, like all depigmenting and abrasive acids, salicylic acid has contraindications and side effects. It can cause hypersensitivity, redness, and inflammation.

In general, 2-hydroxybenzoic acid is a widely used substance in cosmetics and as a base for many dermatological treatments.

What salicylic acid is and what it is used for

It is a hydroxy acid originally isolated from willow bark, hence its name Salix. Salicylic acid is a colorless, solid, and soluble compound.

It is used to treat acne-prone skin and to produce acetylsalicylic acid. It is the raw material for making aspirin and many other pharmaceutical products.

Here is what salicylic acid is used for:

• Treating acne.
• Psoriasis.
• Removing calluses.
• Removing facial warts, plantar warts, flat warts, etc.
• Treating facial spots (skin hyperpigmentation).
• As a treatment to remove the superficial layer of the epidermis (stratum corneum).
• Performing peels.
• Treating keratosis.
• Removing dandruff.
• Complementing psoriasis treatment.

However, salicylic acid, in addition to its medicinal properties widely used in medicine, also has benefits in cosmetics, being one of the most used products to remove facial skin imperfections and as a base for many anti-stain and anti-aging creams.

It is obtained from carbon dioxide and sodium phenoxide, with a strong acid added later to complete the formula. This can be done through the chemical process known as Kolbe-Schmitt synthesis.

But as mentioned, the uses of salicylic acid are numerous, so here we describe them all.

Properties of salicylic acid

• Anti-acne.
• Depigmenting.
• Antiseptic.
• Exfoliating.
• Collagen and elastin regenerating.

It goes without saying that these types of acids are very beneficial when applied topically to certain skin types. The cosmetic and medical properties are numerous, making it widely used by dermatologists and estheticians.

It is usually used in a topical format, applying a small amount to the area where skin regeneration is desired.

Often, beta hydroxy acid (salicylic acid) is recommended by dermatologists to improve the appearance of the face by treating pimples and pustules. It is also used to smooth the texture of the epidermis, remove spots, and correct various facial abnormalities.

Although it is widely used to improve other parts of the body where the skin has any type of pathology or spot such as the armpits, groin, or décolletage, these areas are much more sensitive than the face, so it should be applied with caution.

The depigmenting properties of salicylic acid help to remove the superficial layer of the skin, where spots caused by melanin accumulation, marks, and expression lines, as well as other imperfections such as small warts, calluses, and scars, are present.

It also serves as an exfoliant for the skin. Applying a bit of salicylic acid cream causes peeling, thereby regenerating the entire tissue.

Other benefits of topical salicylic acid include improving pore health. It cleanses dirt and allows the skin to breathe better, causing pores to gradually close after being used as a peel.

Uses of Salicylic Acid

• Acne.
• Peeling.
• Warts.
• Calluses.

For Acne

It works as a treatment to eliminate and prevent the formation of pimples on the face and body. Salicylic acid for acne produces exfoliation and peeling, smoothing the skin and correcting excess facial oil.

It is considered a keratolytic agent and, when applied topically, reduces inflammation and redness caused by pimples on the face.

Salicylic acid for acne opens blocked pores, facilitating the drying of pimples and pustules. Healing takes place over several days, but the results are very good in the end.

How to Use Salicylic Acid for Acne?

1. Apply a small amount of salicylic acid to the affected skin with a gauze or cloth, especially where there is acne vulgaris or pimples.
2. Use 1 or 2 times a day. Always follow the instructions of the brand you purchased or the advice of your doctor.

What to Avoid with Salicylic Acid and Acne?

• Do not apply to cracks or open wounds.
• Avoid when the skin is red.
• Contraindicated for skin infections.
• Never use on large areas of the body.
• Do not apply to sensitive areas such as mucous membranes, near the eyes, or genitalia.
• Be very careful with armpits and groin (only under dermatological recommendation).

Salicylic Acid Peeling

It can be applied as a treatment for the face and body. The salicylic acid peeling is one of the most commonly used today. Its advantages are numerous compared to other AHA acids as it not only provides chemical exfoliation but also disinfects and regulates sebaceous production.

For a deep peeling, it is advisable to apply a keratolytic substance a few days prior, which softens and removes part of the superficial skin layer. After a few days, salicylic acid peeling can fully exert its properties as it will penetrate much better into the skin tissue.

The salicylic peeling removes sebaceous oil, eliminates pimples and acne-related blemishes, and provides a much smoother and blemish-free face.

For it to work properly, it can be used as a preliminary step with tretinoin or glycolic acid. Other cosmetic acids with depigmenting properties are also valid. However, these should never be applied simultaneously. First, apply the keratolytic substance and then, after a few days, the salicylic acid.

The salicylic acid mixture is usually at 30%, although depending on the skin characteristics, it may vary to a concentration of 20%, 10%, etc., if there are many pimples, the tissue is hard like calluses, there are superficial or deep scars, etc.

Once applied, it will start to act, forming a white layer on the skin as it dries. This indicates that it has stopped acting, and therefore, the substance is no longer active and can be carefully removed.

When to Use Salicylic Peeling?

• To treat acne.
• To remove peeling.
• To remove calluses on feet, hands, etc.
• To eliminate warts.
• To clean the pores.

Salicylic Acid for Warts

Salicylic acid is also a fantastic way to remove warts. As mentioned in the section “What salicylic acid is used for,” it has keratolytic properties, which help in the removal of the stratum corneum of the skin, so it can be applied topically to remove imperfections and skin formations caused by the human papillomavirus (HPV).

Salicylic acid for plantar warts, on the face, and other areas works very well. In most cases, it causes the hyperkeratosis to fall off within a few days of use, although it may take several weeks.

Things to Keep in Mind When Removing Warts

Its application differs from that for acne. Instead of moistening the area with gauze, you need to immerse the entire hyperkeratotic tissue, that is, the wart itself. Most treatments come in a small bottle with an applicator, a type of brush. With the applicator, it is possible to coat the entire wart.

Additionally, keep in mind the following:

• Use it preferably at night.
• Cover the area with a bandage or patch for better effectiveness.
• Remove the residue in the morning.
• Do not get it on healthy skin.
• Remove dead tissue every few days. You can use a file or scissors if you see hanging skin. Be careful when handling it, as it may contain active HPV, which causes the wart formation. Dispose of the skin fragments and wash your hands.
• If you notice that the wart area is very sensitive, painful, or has significant redness, you may need to stop using it for a couple of days.

Does It Work for Plantar Warts? And for Facial Warts?

It is effective for all types of warts, acting the same way regardless of their location.

Salicylic acid for plantar and flat warts should be applied as described, and it is always recommended to follow the instructions on the package or those provided by a dermatologist.

Its action is similar for both plantar warts and facial warts, with more care needed in facial areas to avoid side effects on healthy skin.

For this purpose, different brands and commercial names can be purchased, available in the form of gels or lotions.

Wart removal will occur after 2 or 3 weeks.

Salicylic Acid for Calluses and Corns

It is also used to remove calluses on the feet and hands.

When the skin undergoes continuous friction, keratin accumulates to strengthen the tissue. Cell multiplication thickens the epidermis and hardens the skin to prevent it from breaking, making the stratum corneum much thicker and rougher.

Salicylic acid for hard and soft calluses is an excellent treatment. It dissolves the hardened epidermis that has formed over time due to pressure or friction. The surface cells soften and eventually fall off.

Its mode of action is similar to that for warts. Salicylic acid for calluses should be applied topically, often sold as callus pads. The Compeed brand is well-known, but there are also other reputable brands in various countries.

Can It Be Used with Other Remedies for Calluses?

Of course, but always ensure that it is not an acid or liquid product. You can complement the use of salicylic acid for removing calluses with mechanical methods such as pumice stones, files, callus removers, etc.

Do All Salicylic Acid Products and Brands Have the Same Effects?

No. Some are more intense than others and may vary in their concentration of active substance.

You should always check the percentage of salicylic acid, as it is common for it to be used in small amounts and even mixed with other keratolytic substances.

For example, a commonly used brand for treating acne is Neostrata Gel Forte Salicylic Acid. This product also contains glycolic acid, which is one of the alpha hydroxy acids or AHAs that acts as a depigmenting agent and exfoliant. Together, a BHA and an AHA can work very well and enhance the effects, so not all brands are the same and not all salicylic acid products produce the same effects.

It is very important to always review the composition to ensure it is suitable for your skin type or the intended use (acne, warts, exfoliation, etc.).

Some products with 2% salicylic acid will be sufficient to produce depigmentation, while for calluses on the feet and plantar warts, you may need a higher percentage. It also matters if the product contains only 2-hydroxybenzoic acid or includes other types of acid.

Types of Products

• Cream.
• Gel.
• Soap.

The differences between them are in their presentation. While salicylic acid creams are ideal for treating acne and skin imperfections like spots, gels are usually used for calluses.

However, no commercial form is exclusive, meaning each laboratory can manufacture its product in the form it deems most suitable.

Each type of salicylic acid will come with specific instructions that you should always follow.

Is It Always for Topical Use?

Yes. All products for sale are meant to be applied to the surface of the skin. As it is an abrasive acid with organic tissues, you should never ingest it or apply it to open wounds.

In contrast, acetylsalicylic acid is a derivative intended for ingestion.

If you have doubts about whether you can take it or not, always check the instructions or consult a specialist to avoid side effects and issues related to its ingestion.

Is It the Same as Aspirin?

No. Aspirin is acetylsalicylic acid and is considered a medication for pain relief, fever reduction, and as an anticoagulant. Salicylic acid and aspirin are different, although they share some elements in their formulas.

Formulas

• Salicylic Acid Formula: C₇H₆O₃.
• Aspirin Formula: C₉H₈O₄.

As you can see, they have different chemical structures, with salicylic acid having a different formula from acetylsalicylic acid.

Side Effects and Contraindications

After the skin absorbs it, you might experience itching, irritation, burning, and redness in the treated area.

Salicylic acid has side effects in the form of skin peeling.

It is common to notice dryness on the face or in the treated area after several days of use. Small flakes of skin may also appear.

These adverse reactions do not necessarily mean that the product is harmful; in fact, peeling usually indicates that it is working as intended. It does not suggest that you have overlooked any contraindications or that the product is unsuitable.

However, if there is pain, stinging, or severe itching, the formula may be too strong for you.

Here are all the side effects of salicylic acid:

• Itching.
• Irritation.
• Burning.
• Skin peeling.
• Facial spots.
• Avoid using during pregnancy.
• Contraindicated with Sintrom (a medication for diabetic individuals).
• Do not use during pregnancy.
• Avoid during breastfeeding.

How to Avoid Side Effects

A simple way to avoid some of its side effects and relieve skin peeling is by using a moisturizer.

To prevent excessive dryness after using salicylic acid, you can complement the treatment with a moisturizer with hyaluronic acid. This is great for hydration or alternatively, use a cream with aloe vera, which is also soothing and helps with the irritation caused by this acid.

Another option is to use some type of oil, but if you choose this, keep in mind that if your facial skin is oily or if you are using salicylic acid for acne, the effects might be counterproductive. In such cases, a moisturizer might be a better choice than facial oil.

If itching or irritation persists, you should reduce the frequency of use to every 1 or 2 days. It may also be necessary to lower the salicylic acid concentration from 2% to 0.5%. However, only do this if it is not advised by a doctor. If it is, consult with your doctor.

If you are pregnant, you should avoid contact with this substance, even when applied topically. The same applies if you are breastfeeding.

Additionally, you should avoid sun exposure while using salicylic acid in its various forms, whether after a peel, a nighttime cream, or acne treatment. Since the skin is more sensitive, sun exposure may cause spots on the face. Always use sunscreen with depigmenting agents.

Usage Precautions

• Always use sunscreen when undergoing a treatment with salicylic acid.
• If it is not for medical reasons, it is better to use BHAs in cosmetics during the months with less sun. Keep in mind if you go to the snow, enjoy skiing, sailing, or doing outdoor activities as you will receive more solar radiation.

Sometimes, the appearance of skin spots is spontaneous. The purpose of this acid is to eliminate them, but as new melanin is created, you might notice a different coloration. These types of skin imperfections can appear due to genetic, environmental factors, or age.

Recommendations

The most common form is a cream with salicylic acid 0.5% or 2%. Sometimes it is called a lotion, gel, etc. The percentage you need varies from person to person.

If you have never used it before, start with the lowest percentage, i.e., 0.25% or 0.5%. You can then gradually increase as you build tolerance.

Pharmacy products should be applied 1 or 2 times a day. It is also possible once every two days. It all depends on its formulation, potency, and the amount of active ingredient included.

Always review the usage instructions for salicylic acid as each brand may vary in dosage and application methods.

It is important to read the prospectus or informational leaflet that accompanies it. Remember, a cream with a single depigmenting or exfoliating substance is not the same as one that contains several acids and cosmetic keratolytic substances for treating the skin.

If you follow the instructions closely, the benefits of salicylic acid are significant.