Helps fight acne."By exfoliating the top layer of dead skin on the skin’s surface, you minimize the risk that the old, dead skin gets mixed with sebum, which creates acne," says Dr. Hartman. As with any and every product you apply or ingest, there are a few key things to look out for that may signal that glycolic acid isn’t for you. Sometimes the shoe doesn’t just fit. When you begin a glycolic regimen, be mindful of the changes in your skin, for better and for worse. In another study, a triple combination cream consisting of fluocinolone acetonide 0.01%, hydroquinone 4%, and tretinoin 0.05% was used in an alternating sequential treatment pattern, cycling with a series of GA peels, for the treatment of moderate to severe melasma. Spectrometry measurement of the difference in melanin between involved and uninvolved skin confirmed that hyperpigmentation was significantly reduced at 6 and 12 weeks, compared with baseline ( P< 0.001), with evaluations showing improvement of 90% or more by week 12. 36 The concentration of GA used by Hurley et al was low (20%–30%), compared to the 30%–40% GA used by Sarkar et al. 32 This could be a reason for the difference in the results they observed. Abels C, Kaszuba A, Michalak I, Werdier D, Knie U, Kaszuba A. A 10% glycolic acid containing oil-in-water emulsion improves mild acne: a randomized double-blind placebo-controlled trial. J Cosmet Dermatol. 2011 Sep;10(3):202-9. View abstract.

Salicylic acid is a beta hydroxy acid peel. It has a comedolytic effect owing to its lipophilic action. It dissolves intercellular cement, reducing corneocyte adhesion.[ 15] Because of its lipophilic nature, it can penetrate the sebaceous glands, thus affecting follicular keratinization. It also decreases inflammatory lesion count by acting on arachidonic acid cascade. In this study, salicylic–mandelic acid peel group showed significant improvement in inflammatory acne lesions compared to the other two groups. There are two common types of skincare acids: Alpha Hydroxy Acids (AHAs), which work by removing dead cells on the surface of your skin – also referred to as ‘resurfacing’– and Beta Hydroxy Acids (BHAs), which penetrate deep into pores. Glycolic acid is an AHA. As a humectant, glycolic acid draws and retains moisture within the skin to maintain hydration which effectively strengthens the skin barrier and skin health. Acne treatment Zaki NS, Hilal RF, Essam RM. Comparative study using fractional carbon dioxide laser versus glycolic acid peel in treatment of pseudo-acanthosis nigricans. Lasers Med Sci. 2018;33(7):1485-1491. View abstract. If you're just starting to incorporate glycolic acid into your skincare regimen, I would suggest using a gentle glycolic cleanser to get your skin used to it, rather than diving straight into a leave-on glycolic product,’ suggests Dr Tailor. ‘Glycolic acid is most effective when administered as a chemical peel by your cosmetic doctor – they utilise stronger ingredients for more potent effects.’

Sahu P, Dayal S, Bhardwaj N. Topical 5% tranexamic acid with 30% glycolic acid peel: An useful combination for accelerating the improvement in melasma. Dermatol Ther 2021;34(6):e15107. View abstract. Javaheri SM, Handa S, Kaur I, Kumar B. Safety and efficacy of glycolic acid facial peel in Indian women and melasma. Int J Dermatol 2001;40:354-7. View abstract. Commonly used superficial peels. Glycolic acid. The most popular and time-tested superficial peeling agent is glycolic acid, an AHA derived from sugar cane. It is the smallest and simplest AHA in terms of chemical structure, and is also a highly hydrophilic molecule with the greatest bioavailability of all the AHAs. 35 – 37 When properly used, superficial exfoliation with glycolic acid at concentrations of 30 to 50% has demonstrated excellent clinical efficacy in the treatment of superficial hyperpigmentation, mild-to-moderate chrono- and photoaging, and fine rhytides. 1 – 3 , 5 , 7 , 9 , 15 , 17 , 18 , 21 Glycolic acid is often considered the first-line choice of chemical peeling agents for treatment of melasma. 1 – 3 , 5 , 7 , 9 , 15 , 17 , 18 , 21 , 38 , 39 For superficial chemoexfoliation, most concentrations range from 20 to 50%, with higher concentrations (70%) entering the medium-depth category. Glycolic acid is the prototypical non-self-neutralizing AHA (i.e., keratocoagulation will continue to occur as long as the caustic agent remains on the skin). Thus, careful application and diligent observation of time and clinical signs of reaction completion (e.g., erythema and frosting) are essential. Reaction completion of glycolic acid is achieved by introducing an alkaline neutralizing agent (e.g., sodium bicarbonate neutralization). Clinicians should note that neutralization of any acid with any base is an exothermic process; thus, patients should be warned that a transient increase in warmth, burning, or stinging will likely occur during neutralization. Regardless of whatever product you choose, you will see benefits from any concentration percentage, says Dr. Krant. “Glycolic acid works every time you use it, and it begins to work immediately.” Dr. Krant advises to only use products with a maximum concentration of 10% at home. “Stronger formulations can be applied by your board-certified dermatologist in-office, but should only be applied by people with extensive experience and training in chemical peels.” Figure 2 reveals that there was no significant difference in the MASI scores from baseline to the end of the study using treatment with HQ alone compared with HQ plus glycolic acid peels. Similar results were found with MASI scores from color and UV slides. The results of the linear analog scale also revealed that there was no significant difference between the degree of improvement when using HQ alone compared with HQ with glycolic acid peels.

While glycolic acid can be beneficial in conjunction with other, gentler exfoliators like salicylic acid, when combined with stronger exfoliants like retinol, it can be too strong for most skin types,’ warns Dr Tailor. ‘Overall it's actually very safe – so much so that we can use this active ingredient during pregnancy.’ Glycolic acid actively helps to combat active acne inflammations at the exact same time as it works to reduce previous acne scarring. This one-two punch makes it a favourite of acne sufferers the world over.In a pilot study by Burns et al, postinflammatory hyperpigmentation was treated with a series of GA peels in skin types IV–VI. No adverse effects were reported in dark skin, and the GA peel proved to be efficacious. 41 This echoed the study by Grover and Reddu, in which skin types III–V showed overall improvement of skin texture in almost all patients. 24 Nai RS, Ghiya BC, Mohta AK, Mehta RD. A randomized control trial of 20% glycolic acid versus 30% salicylic acid in the management of molluscum contagiosum. J Cutan Aesthet Surg 2022;15(3):249-253. View abstract. Even if you’re not hugely into skincare (i.e. if a simple cleanse, tone, moisturise is enough to please you), it’s likely you’ve come across the words ‘glycolic acid’ plastered across products. From the super luxe to drugstore regulars, most of the major beauty brands have an impressive glycolic offering. Stiller MJ, Bartolone J, Stern R, et al. Topical 8% glycolic acid and 8% L-lactic acid creams for the treatment of photodamaged skin. A double-blind, vehicle-controlled clinical trial. Arch Dermatol 1996;132:631-6. View abstract.