PHAs against brown acne marks.

Even once the blemish has disappeared, acne can leave brown marks on the skin, known as post-inflammatory hyperpigmentation spots. These persistent flat brown or black spots are generated following an increased production of melanin in response to an inflammatory reaction. Indeed, the appearance of these hypercoloured areas relies on the production of inflammatory cytokines, which have pro-pigmenting properties, by the surrounding cells. They will activate the melanocytes (cells producing melanin), leading to a significant release of melanosomes (pigment granules) and thus an excess of melanin. Although this phenomenon can affect all skin types, it is generally more common in individuals with mixed to dark skin (phototypes IV to VI).

Unlike acne scars, these marks are temporary and usually disappear spontaneously without leaving scars after several months (between 3 to 24 months). Sometimes, it can take several years. However, the speed of their disappearance depends on your relationship with the sun, which can prolong the healing time, but also on the difference in skin tone between the colour of the skin and the shade of the mark.

PHAs are keratolytic agents suitable for all skin types, even those that are sensitive, unlike AHAs and BHAs. Indeed, due to their high molecular weights, they remain on the surface of the epidermis. This explains their good skin tolerance compared to other acids which penetrate more deeply into the epidermis.

There are numerous PHAs, here are two particularly common in cosmetic formulas:

• The gluconolactone: This is a PHA naturally present in skin cells. This antioxidant effectively fights against free radicals.

• Lactobionic Acid:This is a derivative of lactose that has a moisturising and soothing effect.

To fade the brown marks left by acne, these peeling agents work by breaking down the bonds between the most superficial skin cells to reorganise the epidermis. They thus accelerate the process of skin peeling and induce the rapid dispersion of melanin granules within the keratinocytes.

In other words, the application of PHA triggers a controlled exfoliation of the epidermis, and with it the melanocytes and the marks left by pimples.

Thus, cosmetic treatments based on acids (A.H.A., B.H.A. and P.H.A.) at low concentrations (up to 20%) can be used to reduce the appearance of post-inflammatory hyperpigmentation marks. However, several applications at a regular pace will be necessary to achieve visible results. In this regard, you can use our anti-mark serums. It specifically targets acne marks and is applied locally. It contains gluconolactone mentioned above and an extract of Centella asiatica, an active ingredient known to help remodel the texture of marked skin.