Why does glycolic acid sometimes irritate the skin?

The effects of this active ingredient are highly variable and depend on the concentration of glycolic acid and the duration of application. That's why it's crucial to always thoroughly read the instructions before any application. Besides the concentration and the application time, the pH of the formula will have an impact on the intensity of the exfoliation. Indeed, the higher the pH, the more the action of the glycolic acid is neutralised.

It's important to understand that it's completely normal to experience slight tingling and a mild warming sensation, and to see redness appear after applying cosmetics containing glycolic acid. This is due to the low molecular weight of this active ingredient, which then penetrates deeply into the layers of the epidermis.

Indeed, depending on your skin's tolerance level, these symptoms can intensify and may even be accompanied by erythema, burning sensations, tightness, itching, facial swelling, and hyperpigmentation. In rare cases, hypopigmentation, persistent erythema, and acne flare-ups have been reported. As soon as such side effects appear, immediately stop using the product and consider rinsing your face thoroughly with water. However, at Typology, we advise against its use onsensitive and reactive skin, as well as for individuals suffering from an inflammatory skin condition (eczema, rosacea, herpes, etc…). It is also advisable to avoid using it in pregnant women. Indeed, it is the cause of vascular disorders related to hormonal impregnation, resulting in congestive flare-ups on the face: the skin reddens more easily and becomes more sensitive.