Azelaic Acid Serum (AZ15) — Reddit Reviews
by Cos De BAHA
Updated September 26, 2026
15% azelaic acid serum for redness and PIE; thick and sticky.
What the community says
A 15% azelaic acid serum with panthenol, ceramide NP, centella asiatica extract, madecassoside, and sodium hyaluronate. Redditors reach for it for redness, PIE, and spot-treating stubborn marks; the catch is the thick, sticky texture and occasional white cast.
What this means for you
What people love
- 15% azelaic acid plus calming extras
- Helps redness, PIE, and red spots
- Barrier helpers: panthenol, ceramide NP, centella
Watch out for
Product details
Skin type data limited
Where to buy
What the science says
Acne
Strong evidence
Azelaic Acid: 22 studies tested it on its own. See all 31 studies
What the studies found
- Most studies found azelaic acid helped clear acne
- It often reduced pimples, blackheads, whiteheads, and red, sore spots
- It usually worked about as well as tretinoin and some other common acne treatments
- Some studies found it worked less well than benzoyl peroxide
- The most common side effects were local skin irritation, peeling, dryness, and stinging
Studied at 5–20%this product: 15%
Hyperpigmentation
Strong evidence
Azelaic Acid: 12 studies tested it on its own. See all 15 studies
What the studies found
- Most studies found azelaic acid helped fade dark spots or patches
- It faded melasma patches better than a placebo in several studies
- It often worked about as well as hydroquinone, and sometimes better than weaker hydroquinone
- It also helped fade dark marks left after acne in one small study
- The most common side effects were mild burning, stinging, itching, redness and scaling
Studied at 15–20%this product: 15%
Research context, not treatment advice. Studies are about the ingredient, not necessarily this exact product.
Real Reddit threads — 10 mentions across 10 threads
Cos De BAHA Azelaic Acid Serum (AZ15) on Reddit, in one place — 10 threads from r/AsianBeauty, r/koreanskincare and 2 more, summarized.
“cos de baha 10% azelaic acid”
Mentioned
“AM: skin1004 centella ampoule, cos de baha 10% azelaic acid, dr g clear soothing cream”
Mentioned
“Cos de BAHA’s Acid Azelaic 15% leaves a white cast on my face”
Cautionary
“I apply this serum by massaging it into my face and then gently patting my cheeks.”
Cautionary
“azelaic acid is just kinda thick and pasty, white cast is pretty normal with it.”
Cautionary
“Cos De BAHA - AZ15 Serum”
Positive
“I just speed-watched a few videos on hyperpigmentation, and decided to throw the kitchen sink of ingredients at it.”
Positive
“I’m using the other products all over.”
Positive
“I recently got my hands on AZ15 from Cos de Baha”
Positive
“I actually prefer Azalea more as a spot treatment.”
Positive
“I was able to purchase Azalea cream over the counter”
Positive
“Cos de Baha is another brand I really like to find individual products or less complicated, affordable products that have never irritated my skin”
Positive
“Azaleic Acid with hyaluronic acid in particular”
Positive
“I think it's worked well for me.”
Positive
“For those who used Cos de BAHA AZ15, what was your experience?”
Positive
“It did help with PIE and minimizing some stubborn red spots on my face, some help (in combination with other things in my routine) with fewer breakouts on the forehead as well.”
Positive
“I've used the 10% version and it was very good for redness but no noticeable improvement in acne.”
Positive
