Chemical Peels for Hyperpigmentation: Which Acids Work?

For chemical peels for hyperpigmentation, which acids have the best support? Glycolic acid has the most data, especially for melasma. A salicylic-mandelic peel makes more sense when active acne and brown post-acne marks occur together. Lactic acid may be easier to tolerate, though results for dark marks are less consistent. TCA carries more risk in head-to-head trials; it isn't a better default. First identify the kind of pigment you're treating.

That answer covers superficial peels done in a clinic. It doesn't mean a home bottle with the same acid can copy a clinic protocol.

Chemical peels for hyperpigmentation: which acids fit?

Hyperpigmentation is a broad label, not one problem. PIH leaves a dark mark after acne, eczema, picking or another skin injury. Melasma often forms broad, matching patches on both sides of the face and tends to return. Sun spots build after years of light exposure. If the pattern isn't clear, first compare the signs of freckles, sun spots and melasma.

This distinction changes the job of the peel. With PIH, you must also stop the acne or rash making new marks. With melasma, removing surface pigment won't stop its light and hormone triggers. A lone patch that changes shape, colour or texture needs a medical check, not an acid.

How the main peel acids compare for facial dark marks

Peel	Best-supported situation	What the evidence found	Practical decision
Glycolic acid	Melasma and broad, surface-level pigment	Sarkar and Lakhani's 2024 review covered 24 studies and 1,075 people. The studies ran 8 to 36 weeks. They judged it the safest and most effective peel studied for melasma.	This is the first acid to discuss for melasma. More studies back it than the other peels, but they can't predict your response.
Salicylic-mandelic acid	Active acne plus brown post-acne marks	Garg and colleagues studied 44 Indian patients with Fitzpatrick skin types IV to VI. After six fortnightly peels, the PIH score fell 59.8% with the combination and 46.3% with glycolic acid by week 24.	The combination matches two problems at once. The small study can't tell us how much benefit came from each acid.
Lactic acid	Melasma when comfort is the main concern	Sahu and Dayal compared glycolic, lactic and TCA peels in 90 people with surface-level melasma. At 12 weeks, lactic acid caused fewer side effects but faded pigment less than glycolic acid or TCA.	Better comfort may come with a smaller effect. The data don't put lactic acid first for stubborn pigment.
Jessner's solution	Melasma treated in a clinic	Jessner's is a blend of salicylic acid, lactic acid and resorcinol. Lawrence, Cox and Brody compared it with glycolic acid on opposite sides of 16 women's faces. Neither side won, and only 11 women completed all three peels.	It worked, but didn't beat the glycolic peel. The tiny study also used pigment medicines between peels.
TCA	Selected dark marks after an in-person check	In Sahu and Dayal's study, TCA matched glycolic acid but caused more side effects. A 2019 trial with 30 people found that adding a TCA spot peel to glycolic acid didn't improve melasma scores and raised side effects.	Deeper isn't always better. TCA is a clinic treatment, not a home step up.

A confirmed, single sun spot is a different case. Chun's team looked back at focal TCA treatment in 106 people with Fitzpatrick types IV and V. Among 49 people with solar lentigines, 42 had a good response. There was no control group or acid comparison. This backs a targeted option from a dermatologist after a skin check, not high-strength TCA at home.

Salicylic acid on its own is often used for acne-prone skin. Yet the direct trial above paired it with mandelic acid. That doesn't prove salicylic acid alone clears PIH better than glycolic acid.

The acid name doesn't tell you the peel depth

Strength, the number of coats and contact time all change how far a peel travels. Skin prep and your current skin state matter too. A daily glycolic toner and a strong peel may share an acid while causing different injuries.

In 2024, the FDA warned people not to use high-strength peels without trained supervision. It cited severe burns, swelling, infection, colour changes and scars. Products sold online included strong TCA, glycolic, salicylic and lactic acid solutions. Don't use a trial's clinic strength as a shopping guide.

Peels also aren't the only way to treat dark marks. A peel sheds surface cells that hold pigment. Ingredients such as azelaic acid or tranexamic acid work in other ways. This comparison of exfoliating acids and brightening ingredients helps you decide whether a peel matches the job.

A worked choice

Illustrative example: You have active clogged pores and flat brown marks exactly where spots healed. There are no matching patches across both cheeks. A clinician may discuss a salicylic-mandelic peel because the closest study included both acne and PIH. If acne is quiet and the pigment is broad, glycolic acid has wider evidence. If the patches match and darken with light, confirming the cause matters more than choosing a stronger acid.

Skin tone doesn't make peels ineffective. It raises the cost of a flare because irritated skin can leave another dark mark. Our guide to post-inflammatory hyperpigmentation in darker skin explains why a slower plan may produce the cleaner result.

What to ask before booking a peel

1. What is the likely cause of my pigmentation?
2. Which acid, concentration and intended depth will you use?
3. How often do you treat my skin tone and people who develop PIH easily?
4. What should I pause before treatment, and when can I restart it?
5. What aftercare will reduce irritation and new pigment?

Before treatment, a provider should ask about inflamed skin, infection, open wounds, past cold sores, scars and current medicines. Niti Khunger's 2008 guideline says to avoid or delay peels for infection, open wounds and inflamed skin. Don't book if the provider can't explain what the mark is, the peel depth and the plan for problems.

Results take a series, and prevention decides whether they last

Most trials didn't test one dramatic peel. They used a series of light peels over about two to six months. Judge change in weeks, not days. Melasma can return, while uncontrolled acne keeps producing fresh PIH.

Light protection is part of pigment treatment. In a 2014 double-blind trial, Castanedo-Cazares and colleagues randomized 68 people with melasma to two SPF 50 or higher sunscreens. Everyone also used prescription hydroquinone. After eight weeks, the sunscreen covering visible light and UV produced 15% more improvement in melasma scores than UV-only sunscreen. This tests added protection during treatment, not sunscreen alone. For melasma, see why iron oxides in tinted sunscreen can matter.

Keep the rest of the routine plain around a peel: gentle cleansing, moisturizer and the sun protection your clinician recommends. Follow written advice about retinoids, scrubs and other acids. Stacking exfoliants to speed fading can create the inflammation you're trying to remove.

For tracking, try one photo before treatment and another every four weeks. Use the same camera, distance, room, lighting and bare skin. This is an editorial tracking method, not a diagnostic test. It can show visible change but can't reveal pigment depth or confirm melasma.

When a peel needs medical help

Brief stinging, redness and flaking can follow a superficial peel. Severe or rising pain, blisters, marked swelling, drainage or fast colour change are not progress. Contact the treating clinic promptly; urgent symptoms need urgent medical care.

See a dermatologist before peeling if a spot is new, changing, irregular, bleeding or unlike your other marks. Get advice if darkening persists despite a careful routine, or if you can't tell whether it is PIH, melasma or another condition. Finding the cause has a higher payoff than choosing the strongest acid.