Glycolic Acid for Skin

Yes, glycolic acid is the smallest acid of the alpha hydroxy acids (AHAs) and is commonly derived from sugar cane. This potent ingredient effectively loosens and releases dead and dehydrated cells, increasing the rate of exfoliation on the surface of the skin. This promotes cellular turnover, and helps minimise the appearance of fine lines, uneven texture, and dull skin tone. The effectiveness of glycolic acid is determined by its free acid value - the active acid available to work on your skin.

Glycolic acid (an AHA) refines the look of oily skin but does not directly control sebum. As an AHA, glycolic acid exfoliates the surface to remove dead skin cells that can mix with oil and clog pores. However, for deeper pore cleansing and oil control, salicylic acid (BHA) is often preferred, as it penetrates pores to help dissolve excess sebum and minimise surface shine. Learn more about building a skincare routine for oily skin.

SkinCeuticals has long been committed to researching innovative and effective sunscreen products. At the same time, we have taken great care to ensure the environmental safety of its products in both salt and freshwater environments. Any ingredient called into question for any reason is taken seriously by our team of toxicologists, clinicians, and chemists, who continuously evaluate each and every ingredient we use.

Overusing any chemical or mechanical exfoliating agent can result in redness or irritation. However, in moderate concentrations, glycolic acid can be tolerated for daily use to help facilitate the skin’s natural exfoliation. When considering a glycolic acid treatment for your skincare regimen, it is important to identify the right concentration for your specific skin concern.

Concentrations of glycolic acid for skin under 4% provide low-level exfoliation and may be used once or twice daily depending on the potency and pH value of the formula. Sometimes glycolic acid may be added to acne formulas at lower levels to enhance skin cell turnover. If looking for an effective nighttime product that primarily targets visible signs of aging such as fine lines, dullness, and skin texture, a 4-10% concentration of glycolic acid is recommended. Any glycolic acid formulation featuring a concentration above 20% should be recommended and administered by a skincare professional. This includes chemical peels, which may require pre-conditioning and specific post-procedure care.

Due to the exfoliating nature of glycolic acid, always apply a broad spectrum sunscreen during the day when using these products.

Not all glycolic acid skincare products are created equal. The free acid value, determined by pH level and concentration, dictates how beneficial the glycolic acid treatment will be in increasing cell turnover. A glycolic acid concentration of 4-10% is ideal for nightly use, but a lower pH is necessary to preserve the strength of the glycolic acid for optimal efficacy. Always look for the free acid value in any glycolic skincare formula, not just the total concentration claimed. As pH levels increase, glycolic acid may become largely neutralised, decreasing the effective acid level and weakening its strength. The key is finding a formula featuring the right balance between glycolic acid concentration and pH levels.

SkinCeuticals Glycolic 10 Renew Overnight Cream provides a unique blend of 10% free acid value glycolic acid, a soothing complex, and 2% phytic acid, delivering an ideal formulation that is safe and effective for improving skin texture, radiance, and overall glow.

A glycolic acid face peel is a chemical peel formulated with glycolic acid as the primary exfoliant in the peel solution. Performed by skincare professionals, these treatments exfoliate and resurface the topmost layer of the skin to reveal new, healthy skin underneath. They are effective in increasing cell turnover, softening the look of fine lines and wrinkles, and improving skin tone and texture. During a glycolic acid peel, one or more layers of the solution are applied onto the skin for a predetermined amount of time based on concentration, skin type, and the patient’s reactivity to the treatment. Once the solution is left on for the desired amount of time, the formula is neutralised with a buffering solution or water.

Following any chemical peel, the skin is more vulnerable to environmental aggressors, making daily sunscreen application a critical step in maintaining protection and supporting recovery. Therefore, proper post-procedure care after a glycolic acid peel is essential, including a high SPF broad-spectrum sunscreen to help shield against damaging UVA/UVB rays. Your skincare professional may also recommend advanced at-home skincare to help maintain and protect the results of your glycolic acid peel.

Yes, it is recommended to use a moisturiser after using a formula containing glycolic acid. We recommend applying a glycolic acid formula in the evening due to the drying effect exfoliants can have on the skin. The evening application will also help to prevent damage from sun exposure.

Yes, glycolic acid and vitamin C can be used together. The combination of these two ingredients works synergistically to rejuvenate the look of skin by removing the outer layer of dead skin cells, which results in the skin accelerating the production of new skin cells. SkinCeuticals C E Ferulic Vitamin C Serum offers advanced protection after a glycolic acid peel by neutralising damaging free radicals. Always apply the formula containing glycolic acid before the formula with vitamin C.

Yes, glycolic acid can increase your skin's sensitivity to sun exposure and damage. As an exfoliant, it removes the top layer of dead skin cells, leaving your skin more vulnerable to UV damage from UVA and UVB rays. It is strongly recommended to always use broad-spectrum sunscreens daily when using skincare formulas containing glycolic acid.

Formulas containing glycolic acid and retinol should not be used in the same application. If you plan to use formulas with both ingredients as part of your skincare regimen, it is recommended that you apply the glycolic acid formula in the morning, then the retinol formula at night. Separating applications will help to reduce possible skin irritation. Check with your physician before usage. Discover how to best use retinol with glycolic acid in your skincare.

Yes, you can use glycolic acid and niacinamide together, but how you layer or alternate them matters. Glycolic acid is an exfoliating alpha-hydroxy acid (AHA) that works best at a low pH, while niacinamide is most stable at a more neutral pH. Using them together in the same routine may reduce their individual effectiveness or increase the risk of irritation for some skin types. Always introduce new skincare products one at a time and monitor your skin's response.

Yes, glycolic acid and hyaluronic acid make a great pairing in your skincare routine. Glycolic acid gently exfoliates the skin, promoting cell turnover, but it can sometimes leave the skin feeling dry. Hyaluronic acid is a powerful humectant that helps to hydrate the skin by drawing moisture into it. SkinCeuticals Hydrating B5 Serum makes a great hyaluronic acid addition to your glycolic acid skincare.

Yes, glycolic acid (AHA) and salicylic acid (BHA) can be used together, but caution is key.

Both are chemical exfoliants; however, they work differently:

• Glycolic acid works on the skin’s surface to improve texture and tone.
• Salicylic acid penetrates deep into pores to reduce oil buildup and prevent breakouts.

At-home glycolic treatments come in the following forms:

Cleansers (≈ 2–8%): Briefest contact; suitable for daily gentle polishing such as Glycolic Renewal Foaming Facial Cleanser.

Toners (≈ 5–10%): Wipe-on, leave-on liquids that prep skin for serums or moisturisers.

Serums (≈ 10–15%): Lightweight leave-ons designed for targeted concerns such as dullness or pigmentation. Like SkinCeuticals Blemish and Age Defence.

Moisturisers (≈ 4–10%): Combine glycolic acid with natural oils and botanicals like Glycolic 10 Overnight Cream.

Among AHAs, glycolic acid penetrates deepest because of its small size, which often leads to quicker results but also a higher chance of tingling or irritation.

Lactic and mandelic acids have larger molecules; they exfoliate more gently and retain more water in the skin, making them good starter acids for sensitive users.

Polyhydroxy acids (PHAs) such as gluconolactone have very large molecules, work mostly at the skin’s surface, and provide additional humectant and antioxidant benefits with minimal irritation.