Lactic Acid (AHA)

Lactic acid is a gentle alpha-hydroxy acid (AHA) that provides dual benefits: it helps promote smoother skin through exfoliation while also supporting hydration. It is one of the best-tolerated AHAs, a good choice for dry skin thanks to its hydrating properties.

• Helps promote smoother, more refined-looking skin texture
• Supports the skin's natural hydration while exfoliating
• Gentler than glycolic acid, making it a good choice for dry skin thanks to its hydrating properties

• An evening step, after cleansing and before moisturizer.
• Your routine sets how often to use it — ease off if your skin starts to feel tight.
• Across the whole face in a thin layer, keeping it away from the eye area. Rinse with plenty of water if any gets in your eyes.
• Follow it with a moisturizer.
• A brief tingle on application is common, most often around the nose. It should settle quickly — if it doesn't, stop using it.
• Wear sunscreen every day while you are using it, and for a week after you stop.
• Keep it to a different evening from other exfoliating acids and from retinol.
• Well-suited for those who find glycolic acid too intense.

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

Six situations change whether Lactic 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

Maternity & Nursing

Go slowly

Prone to Redness

Go slowly

Dry or Itchy Patches

Go slowly

Maternity & Nursing — If you are pregnant or nursing, you may prefer to check with your healthcare provider before use.

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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When should you apply Lactic Acid (AHA)?

An evening step, after cleansing and before moisturizer.

How often can you use Lactic Acid (AHA)?

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

Where do you apply Lactic Acid (AHA)?

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

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

Yes — use sunscreen the next morning.

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

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

Who should avoid Lactic Acid (AHA)?

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

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

Yes. The maximum strength for Lactic 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, 2.5% (pH ≥5.0 — guidance, not law) in the European Union and 2.5% (pH ≥5.0 — 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.