Lactic Acid (AHA)
INCI: Lactic Acid
Lactic acid is an AHA with a larger molecule than glycolic acid, so it penetrates more gently — it exfoliates and improves texture with less irritation risk, which makes it a reasonable entry point into AHAs for sensitive or beginner skin.
How it works
An alpha-hydroxy acid that breaks down superficial desmosomal junctions while concurrently functioning as an intrinsic part of the skin's natural moisturizing factors. It accelerates epidermal desquamation to sweep away pigment clusters while pulling hydration into newly uncovered surface strata.
In practice, that gentler penetration is why it's often recommended as the first acid someone tries, before stepping up to something stronger like glycolic acid.
How to introduce it
Wait about 15 minutes before the next step. Judging Lactic Acid (AHA) before week 8 means judging it before it's had time to actually work — most of what reads as "this isn't doing anything" in the first couple of weeks is just too early to tell.
Possible purging window: weeks 1–3 — temporary increased breakouts as turnover speeds up, not a sign to stop. A purge shows up as small whiteheads in areas you already tend to break out, and settles down on its own within that window. That's different from a bad reaction, which shows up as redness, burning, or swelling in places you don't normally break out, doesn't improve with time, and is a reason to stop — see below.
- Patch test 48 hours before first facial use.
- Sunscreen is mandatory every morning an AHA was used the night before.
- Never combine with retinoids or benzoyl peroxide in the same session.
- Do not layer with vitamin C in the same session — alternate nights instead.
- Do not apply to broken, sunburned, or actively irritated skin.
- — Stinging past 60 seconds.
- — Visible redness the next morning.
Who should be careful
Lactic Acid (AHA) is rated moderate risk. Patch test on your inner forearm 48 hours before first facial use, especially if your skin reacts easily to new products.
Don't combine with
Same-night use can irritate skin or cancel out the active — alternate nights instead of layering them together.
Check your own products for conflicts →Common in these product forms
Among the products Skinzy tracks in India that contain Lactic Acid (AHA), it most often shows up as a serum.
Questions people ask
A gentler AHA than glycolic acid — a reasonable first exfoliating acid for sensitive or beginner skin.
Most people see a fair result around 8 weeks of consistent use — judging earlier usually means judging too soon.
At night. Lactic Acid (AHA) is intended for PM use.
Lactic Acid (AHA) shouldn't share a routine step with: Retinol, Adapalene, Retinaldehyde, Tazarotene, Tretinoin, Trifarotene.