Can glycolic acid be used for lip care?

Glycolic acid, characterised by its low molecular weight, penetrates deeply into the skin to dissolve the intracellular bonds holding dead skin cells together, thereby promoting effective exfoliation. This property is particularly advantageous for facial skin, notably in thicker, more resilient regions, where it reveals newer, healthier layers beneath, thereby evening out skin tone and reducing hyperpigmentation. These same attributes suggest potential benefits for the lips, which commonly suffer from flakiness, dryness and uneven pigmentation.

Unlike traditional mechanical exfoliants, such as sugar scrubs, glycolic acid affords a chemical exfoliation that is more uniform and less abrasive, potentially resulting in smoother, softer lips with more even pigmentation and a more youthful appearance.

Additionally, glycolic acid’s water solubility enhances hydration and moisture retention by binding water molecules, which is crucial for the lips, as they naturally lack oil glands. This hydration, combined with cellular turnover and improved circulation, can lead to a plumping effect. Moreover, glycolic acid helps prepare the skin to better absorb other beneficial ingredients from skincare products and contributes to improved barrier function. Its ability to stimulate collagen production and accelerate cell renewal also helps in minimising the appearance of fine lines around the lips, making it an effective ingredient for maintaining a more youthful, defined lip contour.

However, the lips present unique challenges due to their more vulnerable mucosal surface and lack of the protective stratum corneum, the outermost layer of the skin, necessitating cautious application to prevent irritation while maximising these benefits. The potential effects are promising but require further scientific investigation to confirm these effects.

While there is a considerable amount of research on the utilisation of glycolic acid in the perioral area (the area around the mouth), which provides a sound basis, direct studies on the safety and benefits of application to the lips are sparse. The lips’ heightened delicacy and the potential complications arising from contact with saliva or ingestion demand considerable caution. Ingesting glycolic acid, even in small quantities, can cause gastrointestinal irritation, oral burns or allergic reactions. Repeated exposure to low levels of glycolic acid may result in more severe irritation and potential damage to the digestive lining, as well as systemic toxicity. This is why it is essential to read product instructions carefully and ensure that you use items explicitly labelled for the lips. If accidental ingestion or irritation occurs, rinse immediately and seek medical advice.

Dermatologists recommend using glycolic acid at lower concentrations to minimise the risk of irritation. Suitable product selection is crucial, emphasising formulations specifically declared safe for application to the lips. Experts state that best practices for using glycolic acid on the lips include utilising very low concentrations, which are more suitable for the sensitive skin of the lip area. It is advisable not to leave the product on for prolonged periods; a brief application of 5 to 10 minutes is sufficient to gain the benefits without causing undue irritation. Following the application, the product should be wiped off gently, and a hydrating moisturiser should be applied immediately to soothe and protect the lips.

To minimise the risk of sun damage, treatments should preferably be carried out at night. This timing reduces exposure to UV radiation when the skin is most vulnerable due to the exfoliating effect of glycolic acid. During the day, applying a lip balm with SPF is crucial to protect the newly exposed skin from heightened UV sensitivity.

A key contraindication for glycolic acid treatments is the presence of active herpes simplex virus outbreaks or similar skin conditions. The application of glycolic acid during such outbreaks may exacerbate the condition. It is vital to initiate treatments sparingly and to increase the frequency only in accordance with tolerability and provided that no adverse reactions manifest.

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