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Glyoxylic Acid

INCI: GLYOXYLIC ACID

Reviewed by Emma · Last updated 14 Aug 2026

A chemical compound used primarily in hair treatments, with limited skincare research

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What Is Glyoxylic Acid?

Glyoxylic acid is a small organic acid that functions as a buffering and antistatic agent in cosmetic formulations. It is structurally similar to glycolic acid but contains an additional ketone group, which alters its chemical behaviour and absorption profile.

In skincare, glyoxylic acid appears in formulations intended to address similar concerns as other chemical exfoliants, though it is considerably less common in facial products than its better-studied counterpart, glycolic acid. It is more frequently found in hair-straightening and hair-waving treatments.

How It Works

As a hydroxy acid, glyoxylic acid works by gently dissolving the bonds between dead skin cells on the skin's surface, promoting their shedding. This process is known as chemical exfoliation. The mechanism is comparable to glycolic acid, though the specific molecular structure may influence how readily it penetrates the skin barrier and how it is metabolised once absorbed.

Clinical Evidence & References

Evidence regarding glyoxylic acid's safety and efficacy in skincare is limited. Most available research focuses on its use in hair-straightening products rather than facial formulations. Recent studies have raised concerns about systemic absorption of glyoxylic acid from topical hair treatments, with evidence suggesting it can be converted to oxalate in the body, potentially affecting kidney function in susceptible individuals or with prolonged exposure.

At present, there is insufficient published data to draw firm conclusions about safety or efficacy when used in skincare concentrations. Further research would help clarify its behaviour on facial skin and appropriate usage parameters.

How to Use

If using a product containing glyoxylic acid, introduce it gradually into your routine and follow the product instructions carefully, particularly regarding application time and frequency. Patch testing is advisable. As with all exfoliating acids, consistent use of broad-spectrum SPF 30 or higher is essential, since exfoliation increases sun sensitivity.

Safety & Precautions

Glyoxylic acid can be absorbed through the skin and metabolised to oxalate. Whilst occasional use in skincare products is unlikely to pose risk to most individuals, caution is warranted, particularly with repeated or prolonged exposure. Those with compromised kidney function should exercise particular care.

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