Glycolic Acid (AHA)

Glycolic acid is the smallest and most well-researched alpha-hydroxy acid (AHA). It works at the outermost surface of the skin, helping promote a smoother, brighter-looking finish. As a leave-on serum, it stays on the skin rather than rinsing away.

• Helps promote a smoother, brighter-looking skin surface
• Supports the appearance of a more refined, even-looking skin tone
• One of the most widely used exfoliating ingredients

• An evening step, after cleansing and before moisturizer.
• Sweep it across the face rather than dabbing it on single spots, and keep it away from the eye area. Rinse with plenty of water if any gets in your eyes.
• Ease in gradually — your routine sets the pace, and there is no benefit to going faster than your skin is comfortable with.
• Expect stinging or tingling on application in the first few weeks. That is the thing to watch: if it stays sharp, or you get dryness and tightness, use it less often rather than pushing through.
• Follow it with a moisturizer. Hydrating and barrier ingredients like hyaluronic acid and ceramides sit well alongside it.
• Wear sunscreen daily while you are using it, and for a week after you stop — the extra sun sensitivity outlasts the product.
• Use one exfoliating product per session. Keep it to a different evening from other acids, from scrubs and enzyme masks, and from retinol.
• Darker skin tones can be more prone to temporary uneven tone from strong actives — keep an eye on how your skin responds, especially early on.

This product contains an alpha-hydroxy acid (AHA) that may increase your skin's sensitivity to the sun. Use a sunscreen while using this product and for a week after you stop. Discontinue use if irritation occurs and consult a healthcare provider.

Six situations change whether Glycolic Acid (AHA) suits your skin right now. Each one is either a reason to skip it, a reason to go slowly, or nothing to watch for.

Fragile or Sensitive

Skip it

Recent Facial or Laser

Skip it

Recent Shave or Wax

Skip it

Prone to Redness

Go slowly

Dry or Itchy Patches

Go slowly

Maternity & Nursing

No caution

Prone to Redness — Try it on a small area first, and use it less often — or stop — if you notice stinging or extra redness.

Dry or Itchy Patches — Keep the rest of your routine well moisturized, and use it less often — or stop — if you notice tightness or itching.

These are the maximum strengths allowed or advised in each market — some are set in cosmetics regulation, others are the ceiling a cosmetic safety panel recommends. They are limits, not targets — the right strength for a formula is the formulator's decision.

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Glycolic acid exfoliating serum · 3

Cos De BAHAGlycolic Serum (G) - 30ml$9.58APLBGlycolic Acid Niacinamide Ampoule Serum - 40ml$9.80Esthetic HouseToxheal Red Glycolic Peeling Serum - 100ml$13.31

When should you apply Glycolic Acid (AHA)?

An evening step, after cleansing and before moisturizer.

How often can you use Glycolic Acid (AHA)?

3× a week to daily, all over, not the eye area.

Where do you apply Glycolic Acid (AHA)?

All over, not the eye area. Keep it off your lips too.

Does Glycolic Acid (AHA) make skin more sensitive to the sun?

Yes — use sunscreen the next morning.

What should you not use with Glycolic Acid (AHA)?

Space it apart from Azelaic acid, Cysteamine, Eye-area retinol, Other exfoliants, Retinoids and Vitamin C.

Who should avoid Glycolic Acid (AHA)?

Skip it if any of these apply: Fragile or Sensitive, Recent Facial or Laser and Recent Shave or Wax. Go slowly with Prone to Redness and Dry or Itchy Patches.

Is there a cosmetic limit for Glycolic Acid (AHA)?

Yes. The maximum strength for Glycolic Acid (AHA) in a cosmetic is 10% (pH ≥3.5 — guidance, not law) in the United States, 18% (total mono-AHA, pH ≥3.5) in Canada, 4% (pH ≥3.8 — guidance, not law) in the European Union and 4% (pH ≥3.8 — guidance, not law) in Great Britain. A cap is a limit on the rules, not a signal to use more.

Everything on this page traces to the sources listed below — regulators' own publications and published studies. Where the evidence does not answer a question, it is left unanswered.

Some sources below are the official product information for prescription medicines — some contain this ingredient at higher strengths, others are cited for how they interact with it. We use them for their safety and handling detail only. A cosmetic product is not one of those medicines and is not intended to treat any condition.

Our review is AI-assisted and is not a named expert's opinion. Last reviewed August 7, 2026.

Think something here is out of date or wrong? Email us at wiki@skinintelligence.ai with your reasoning and where you read it. We read what people send, and we update the page when the sources support it.