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Compatibility  /  AHAs (glycolic / lactic acid)

AHAs (glycolic / lactic acid)

INCI · Glycolic Acid

An alpha-hydroxy acid that exfoliates for a smoother-looking surface; usually evening.

What AHAs (glycolic / lactic acid) layers with
Copper peptides (GHK-Cu)

Low-pH exfoliating acids are commonly kept apart from copper peptides, since the acidic environment is thought to disturb the copper complex. Use the acid on its own evening and the peptide another time.

Separate — AM / PM
Argireline

Some keep peptides away from low-pH acids as a precaution; the concern is theoretical for finished products.

Use with caution
Matrixyl

The pH concern with peptides and acids is often repeated but not well-established; separate if your skin prefers.

Use with caution
SNAP-8

Precautionary rather than established — many routines combine peptides and acids without issue.

Use with caution
Vitamin C (L-ascorbic acid)

Both are low-pH actives; layering can raise the chance of stinging for some skin. Introduce slowly or alternate.

Use with caution
Retinoids (retinol)

Layering a retinoid with an exfoliating acid raises the chance of visible irritation for many people; alternating on different nights is common.

Use with caution
BHA (salicylic acid)

Combining exfoliating acids increases total exfoliation and the chance of over-doing it — use sparingly and not every day.

Use with caution
Benzoyl peroxide

Two strong actives together can be drying or irritating for some; introduce slowly.

Use with caution
Niacinamide

Generally fine; niacinamide is well tolerated alongside exfoliating acids.

Compatible
Hyaluronic acid

No specific interaction noted — generally fine to layer in a cosmetic routine. Patch-test new combinations.

Compatible
Vitamin E

No specific interaction noted — generally fine to layer in a cosmetic routine. Patch-test new combinations.

Compatible
Azelaic acid

No specific interaction noted — generally fine to layer in a cosmetic routine. Patch-test new combinations.

Compatible
Sunscreen (SPF)

No specific interaction noted — generally fine to layer in a cosmetic routine. Patch-test new combinations.

Compatible
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Region — United States
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AHAs (glycolic / lactic acid): what layers with it · Vallydia