Glycolic Acid
Exfoliates rough skin and can modestly improve signs of sun damage.
Key facts
Glycolic Acid at a glance.
Helps with
Dullness, fine lines and uneven tone
Results
Assess at 8–12 weeks
Skin tolerance
Stinging or irritation
Routine fit
Start a few evenings weekly
At a glance
Top things to know about Glycolic Acid
- What it is. Alpha hydroxy acid (AHA).
- What it does. Exfoliates rough skin and can modestly improve signs of sun damage.
- What limits the claim. An older 22-week vehicle-controlled trial supports modest photoaging benefits from 8% cream. Results from 50% peels cannot be transferred to everyday serums.
- Choosing a formula. Choose for rough texture and dullness; start with a mild leave-on formula.
More details: strength, timing and precautions
| Bottom line | Choose for rough texture and dullness; start with a mild leave-on formula. |
|---|---|
| Type | Alpha hydroxy acid (AHA) |
| What it does | Exfoliates rough skin and can modestly improve signs of sun damage. |
| Best for | Dull Skin; Wrinkles and Fine Lines; Sun Spots |
| Studied concentrations | 8% leave-on cream and 50% professional peels in separate trials. |
| When to use | Start on a few evenings weekly; increase only if comfortable. |
| Time to results | Often 8–12 weeks in small cosmetic studies; results may be subtle |
| Irritation | Stinging, peeling and irritation are possible, particularly on inflamed skin. |
| Sensitive skin | Choose a simple formula and test a small area first. Avoid actively inflamed or broken skin unless the product is specifically directed for it. |
| Available | Cosmetic or OTC products; some high-strength procedures are separate treatments. |
Often used for
What Glycolic Acid is used for
Dull Skin
Exfoliation can smooth rough texture and improve the look of dull skin.
Wrinkles and Fine Lines
An 8% cream produced modest improvements in photodamaged skin.
Sun Spots
A small professional-peel trial found slight lightening of sun spots.
Keratosis Pilaris
The reviewed sources do not establish this ingredient as a treatment for this concern.
Rosacea
The reviewed sources do not establish this ingredient as a treatment for this concern.
Eczema
The reviewed sources do not establish this ingredient as a treatment for this concern.
Ice Pick Scars
The reviewed sources do not establish this ingredient as a treatment for this concern.
HOW IT WORKS
How Glycolic Acid works
Diagram explanation and sources
Acts at the outer skin: Acidity helps loosen adhesion between dead cells. Promotes surface shedding: Texture changes depend on pH and the formula.
Schematic illustration; not a measurement of skin penetration. Effects vary with ingredient identity and formulation.
Strengths
Glycolic Acid strengths
Home skincare and office peels use very different glycolic acid strengths. Clinical studies include 8% leave-on cream and professional peels from 20% to 70%.
8%
20–70%
Studied for sun-damaged skin. Use a finished home product as labeled; this does not establish a universal ideal percentage.
Serial office peels have used these strengths for selected concerns. These are controlled procedures, not home-use targets.
Choosing a strength: Choose a home product for your concern and skin tolerance. Ask a qualified clinician whether an office peel is appropriate.
Higher strengths: High-strength peels can cause burns, scars and lasting color changes. Do not copy a study’s peel concentration or timing at home.
Formula matters: Acidity, neutralization, contact time and layers influence peel depth. Two products with the same percentage can act differently.
Forms
Glycolic Acid forms
Toner
A watery liquid that spreads easily and layers lightly. Alcohol, fragrance and other ingredients influence stinging or dryness.
Serum
A light liquid or gel that spreads in a thin layer. Can suit layering; it may not provide enough moisture on its own.
Pads
Pads carry liquid across the skin without pouring. Rubbing can add friction, especially on sensitive or irritated skin.
Peel solution
A liquid vehicle used for controlled exfoliation. Acidity, contact and the full formulation affect skin feel and tolerability.
Products
Product examples
The INKEY List Glycolic Acid Toner
Paula's Choice 8% AHA Lotion Exfoliant
Paula's Choice RESIST Daily Smoothing Treatment With 5% AHA
How to use it
When to use
Start on a few evenings weekly; increase only if comfortable.
How to apply
Apply a thin layer to clean skin using the amount on the product label.
Moisturizing
Use a simple moisturizer if needed; for rich oils or balms, start with a small amount.
Tolerance
Stinging, peeling and irritation are possible, particularly on inflamed skin.
If it is not working
Reassess after roughly 8–12 weeks, or sooner for worsening symptoms. Persistent pigment, acne or a rash may need a different treatment.
Sun protection
Use broad-spectrum SPF 30 or higher each morning, especially when treating uneven pigmentation.
What to expect
First few weeks
Assess tolerance and texture; immediate softness can come from the base formula.
4–8 weeks
Subtle changes may appear in some tested products; evidence varies.
8–12 weeks
Compare photographs in the same lighting and reassess benefit.
3–6 months
Photoaging trials often need several months; expect modest rather than dramatic change.
6–12 months
Long-term evidence is limited for many cosmetic actives; continue only if useful.
What it pairs with
| Ingredient | Use | What to know |
|---|---|---|
| Moisturizer | As needed | Choose a simple formula that improves comfort. |
| Sunscreen | Each morning | Use a tested broad-spectrum product; do not mix other skincare into it. |
| Other active treatments | Introduce separately | Compatibility does not prove an added benefit. Seek a treatment plan when combining medicines. |
Alternatives
Alternatives
Lactic acid
A larger molecule, so it works more slowly and stings less, and it holds water in the skin while it exfoliates. Glycolic acid acts faster on rough texture.
Mandelic acid
The gentlest of the common AHAs and less likely to irritate skin into making dark marks. It is slower, and much less studied.
Polyhydroxy acids
Considerably gentler, hydrating, and they have not been shown to increase sun sensitivity. They also do less, more slowly.
Salicylic acid
Oil-soluble, so it works inside the pore, which makes it a better fit for blackheads and acne. Glycolic acid does more for surface tone and texture.
Retinoids
They work deeper and do considerably more for fine lines and acne over time, but they take longer, need a prescription at higher strengths, and are stopped in pregnancy.
Professional glycolic peel
Same ingredient at much higher strength, with a short contact time and someone trained watching the skin. Faster, and with a higher risk of pigment change.
Physical scrubs
Cheaper and instant, but the result is surface polish only, and scrubbing is a common cause of irritation.
Safety and cautions
Common reactions
Stinging, peeling and irritation are possible, particularly on inflamed skin.
When to stop
Stop for persistent burning, swelling, blistering or a new rash. Seek urgent care for breathing difficulty or a severe allergic reaction.
Sensitive or inflamed skin
Choose a simple formula and test a small area first. Avoid actively inflamed or broken skin unless the product is specifically directed for it.
Important limits
Do not use a cosmetic product as a substitute for diagnosis of an unexplained, changing or persistent skin problem.
Pregnancy
Very little is absorbed through the skin and it is commonly used, but this is not a decision to make from a webpage. Ask the doctor managing your pregnancy.
Questions
Questions you might be asking.
What should I choose glycolic acid for?
Choose for rough texture and dullness; start with a mild leave-on formula.
How strong is the evidence?
An older 22-week vehicle-controlled trial supports modest photoaging benefits from 8% cream. Results from 50% peels cannot be transferred to everyday serums.
Sources
Sources and further reading
Research updated 2026-10-25. Evidence grades reflect confidence in a specific benefit, not its size.
- Topical 8% glycolic acid and 8% L-lactic acid creams for the treatment of photodamaged skin. A double-blind vehicle-controlled clinical trial. (1996)
- Clinical improvement of photoaged skin with 50% glycolic acid. A double-blind vehicle-controlled study. (1996)
- FDA alpha-hydroxy acid sun-sensitivity guidance
- Trial of serial 20–70% glycolic acid office peels
- Glycolic acid concentration and pH in human skin explants
- FDA: professional supervision for chemical peels
Related
Keep exploring.
Lactic Acid
Mandelic Acid
Polyhydroxy Acids
Salicylic Acid
Keratosis Pilaris
Sun Spots
Wrinkles and Fine Lines
Eczema
Rosacea
Glycolic Acid vs Lactic Acid
Glycolic Acid vs Mandelic Acid