Salicylic acid

This aromatic beta-hydroxy acid occurs naturally in willow bark and other plants, but cosmetic-grade salicylic acid is usually produced synthetically to ensure precise purity. It is more soluble in alcohols and glycol carriers than in water. At a low pH, it acts as a keratolytic ingredient and is one of the most extensively studied actives for oily and acne-prone skin.

Salicylic acid penetrates the oily environment within pores, loosens the bonds between dead skin cells and helps reduce the formation of comedones. It also has an anti-inflammatory effect, so it may reduce the redness of blemishes. At the right dose, it smooths skin texture, but overuse leads to dryness, stinging and disruption of the skin barrier. It should not be used alongside several strong exfoliants at once.

We recommend it for oily, combination, acne-prone and thickened skin with blackheads and blocked pores. Dry or sensitive skin can benefit from targeted, less frequent use. Extra caution and professional advice are needed for anyone with a salicylate allergy or extensively damaged skin, and for young children.

A randomised clinical study showed that 2 per cent supramolecular salicylic acid achieved similar efficacy in mild to moderate acne to a combination of 5 per cent benzoyl peroxide and 0,1 per cent adapalene, and was well tolerated (Journal of Cosmetic Dermatology, 2019). Conventional 2 per cent formulations also have long-term data supporting their ability to reduce comedones.

In Europe, it is commonly used in leave-on cosmetics within the permitted limit, often at 0,5 to 2 per cent depending on the purpose and product category. Its effectiveness depends on the pH and the proportion of free acid. SPF protection is needed during the day, and the frequency of use should be reduced if redness occurs.

When introducing targeted skincare with active ingredients, it is best to start gradually and avoid changing several products at once during the first few weeks. This makes it easier to distinguish results from irritation. Visible changes in texture or tone usually require several weeks of regular use. Daily SPF protection, gentle cleansing and a well-functioning skin barrier have a significant influence on achieving good, lasting results.