Allantoin: What should we know about this active ingredient?

Theallantoin is a highly praised ingredient in skincare for its numerous benefits.

• Allantoin and its healing properties.

  Healing is a natural skin repair phenomenon that can take several weeks. Allantoin is an active ingredient often known to boost the healing process. A 2010 study suggests that it plays a role in fibroblastic proliferation and the synthesis of macromolecules that make up the extracellular matrix.

• Allantoin combats cellular ageing.

  Indeed, it has the ability to stimulate fibroblasts, cells responsible for the production of collagen. However, with age, the rate of collagen production decreases and tends to promote the appearance of wrinkles. Although this property is mentioned in scientific literature, its mechanism of action on fibroblasts is not detailed and remains unknown.

• Allantoin to promote cellular regeneration.

  Thanks to its keratolytic action, it would help to soften the horny layer by promoting the removal of dead cells. Allantoin would eliminate corneocytes by loosening the intercellular cement or desmosomes (protein bridges), which maintain the adhesion of corneocytes to each other. By removing dead cells on the surface of the epidermis, allantoin helps to reduce pore obstruction and eliminate dandruff.

• Allantoin and its anti-inflammatory activity.

  In 2021, a study demonstrated that a fraction of snail mucus containing allantoin exhibited inhibitory activity against the thermal denaturation of human serum albumin, an anti-inflammatory compound. This property could be beneficial in reducing inflammation caused by theacne or an irritated scalp. However, further research is required to substantiate this anti-inflammatory activity.

• The effect of allantoin on sebum.

  Acne is often caused by an overproduction of sebum or the production of excessively thick sebum. Studies suggest that allantoin is capable of eliminating excess sebum. This property would be beneficial for acne-prone skin, but also for oily hair, which tends to produce more sebum (hyperseborrhea).

• The moisturising properties of allantoin.

  It has been mentioned in several studies that allantoin possesses moisturising properties, although its mode of action is not detailed. Its hydrating potential could be explained, as it is a water-soluble humectant ingredient that helps to increase the water content of cells by combating transepidermal water loss in the dermis. This property is interesting to counteract skin and hair dehydration by creating a protective layer around the cuticle.

Due to its softening and hydrating properties, allantoin is considered safe for skin care. The United States Food and Drug Administration (FDA) has listed allantoin as an effective and safe agent for skin protection at concentrations of 0.1 to 2%. In Europe, this active ingredient is not regulated for its use in cosmetic care. It is non-toxic, non-allergenic and non-irritating. As it regenerates skin tissues following injuries or lesions, hydrates the skin, and soothes irritations and itching associated with skin inflammation, allantoin is suitable for all skin types, even delicate and reactive skins.

Allantoin generally does not cause adverse effects when used according to the instructions on the label. However, it is not ruled out that topical treatments may cause irritation or an allergic reaction, especially if they contain other ingredients. As a precaution, it is recommended to perform a skin test in the crook of the arm to observe if a potential allergic reaction occurs. It is advisable to stop using a treatment containing allantoin if one or more of the following reactions occur: inflammation, redness or discolouration of the skin, dryness, itching, or hives.