Cos De BAHA Azelaic Acid 10% Serum with Niacinamide
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What it is
The Cos De BAHA Azelaic Acid 10% Serum is a lightweight, water-based treatment that combines a clinically recognized concentration of azelaic acid with niacinamide to target breakouts, uneven tone, and excess oil in a single step. Azelaic acid is a naturally occurring dicarboxylic acid used in both over-the-counter and prescription skincare for its multi-action profile — antimicrobial, anti-inflammatory, and melanin-inhibiting. This Korean-formulated serum keeps the ingredient list focused, making it a practical choice for shoppers who want actives without unnecessary fillers.
Who it's for
This serum is best suited to oily, acne-prone, and combination skin types dealing with active breakouts, post-acne dark spots (post-inflammatory hyperpigmentation), or congested pores. It works particularly well for people who find stronger acids too sensitizing but still want a meaningful exfoliating and brightening effect. Those managing recurring hormonal breakouts or stubborn PIH that hasn't responded to vitamin C alone may find the azelaic acid and niacinamide pairing more effective for their specific pattern.
Who should skip it: anyone with a known sensitivity to azelaic acid or with a highly reactive, compromised barrier should patch-test carefully or consult a dermatologist first. Pregnant or nursing individuals should confirm safety with their provider before using actives. Very dry or eczema-prone skin may find the formula insufficient on its own without a supporting moisturizer.
How to use it
Apply after cleansing and toning, before heavier creams or oils — serums with active acids absorb best on clean, slightly damp skin. Start by using it three nights a week to assess tolerance, then work up to daily or twice-daily use as your skin adjusts. Because azelaic acid can cause mild transient stinging or redness when first introduced, gradual adoption reduces the chance of unnecessary irritation.
In the morning, always follow with a broad-spectrum SPF 30 or higher — azelaic acid does not increase photosensitivity the way AHAs do, but sun protection is non-negotiable when treating hyperpigmentation. Avoid layering with high-concentration vitamin C (L-ascorbic acid at low pH) in the same step, as the combination can feel uncomfortable on sensitive skin; use one in the morning and the other at night instead.
Key ingredients
Azelaic acid (10%): This concentration sits at the upper end of what is legally available over the counter in the US. Azelaic acid works through three documented mechanisms: it disrupts the cell wall of acne-causing bacteria (Cutibacterium acnes), reduces keratinocyte buildup in pores that leads to comedones, and inhibits tyrosinase — the enzyme that drives excess melanin production in post-inflammatory dark spots. Its anti-inflammatory action also helps calm the redness associated with papules without the dryness of benzoyl peroxide.
Niacinamide: A well-researched form of vitamin B3 that complements azelaic acid on multiple fronts. Niacinamide helps regulate sebum output, reduces the transfer of melanin to skin cells (contributing to a more even tone over time), and supports the skin barrier — which matters when you're using an active acid regularly. The pairing addresses oiliness and discoloration simultaneously rather than requiring two separate products.
Pros & cons
- 10% azelaic acid is a meaningful, effective concentration for acne and PIH management
- Niacinamide adds complementary oil control and barrier support
- Lightweight texture layers easily under moisturizer and SPF
- Well-reviewed by a large base — 4.3 out of 5 stars across roughly 7,800 ratings — suggesting consistent real-world results
- Suitable for daily use once skin is acclimated
- Can cause transient tingling or mild redness during the first few weeks of use
- Results for hyperpigmentation require consistent use over several weeks — not a fast-fix treatment
- Does not contain additional hydrating actives like hyaluronic acid, so dry skin types will need a separate moisturizer
- The formula is not fragrance-free verified for all batches — check current labeling if you are fragrance-sensitive
How it compares
If your primary concern is brightening and antioxidant defense rather than acne, a vitamin C serum may serve you better as your main treatment. The TruSkin Vitamin C Serum with Hyaluronic Acid & Vitamin E adds L-ascorbic acid and hyaluronic acid to the brightening equation, making it a stronger pick for dullness and photoaging — but it lacks the antimicrobial action you get from azelaic acid. For skin that needs hydration alongside tone correction, the Tree of Life Hyaluronic Acid Serum fills that moisture gap and can be layered directly after this serum. The Cos De BAHA formula holds a distinct advantage when active acne and PIH are both present, because no vitamin C serum addresses bacterial overgrowth or keratin buildup the way azelaic acid does.
The verdict
For oily or acne-prone skin managing breakouts and the dark spots they leave behind, the Cos De BAHA Azelaic Acid 10% Serum delivers a well-matched pair of actives in a no-frills format. The 10% azelaic acid concentration is doing real work — it is not a trace-level ingredient dropped in for marketing — and the addition of niacinamide makes the formula more versatile than single-active competitors. It is not a moisturizer, not a fast-acting spot treatment, and not a replacement for medical care if your acne is severe. Used consistently as part of a basic routine — cleanser, serum, moisturizer, SPF — it is a straightforward, honest performer for the concerns it targets.
What shoppers say
Shoppers with rosacea and post-inflammatory erythema report noticeable calming and clearing, with several noting visible improvement in dark spots and uneven texture within weeks. The formula gets consistent praise for feeling hydrating rather than harsh, and many buyers have repurchased multiple times, finding a single bottle lasts one to three months depending on usage.
The main caveat: the one-drop application guidance undersells how much product most people actually need—three to four drops is a more realistic estimate for face and neck, which can affect how long each bottle lasts. Reviewers with very dry or thirsty skin should factor that into expectations.
I have moderate papulopustular rosacea, and with it comes the little white pore plugs that anyone within 3 feet can see under my makeup. It gave my skin a rough texture all over, especially on my nose and chin. These were very much like blackheads, only white and they stuck out of my pores and looked like little slivers if pulled out with tweezers. These were all over my face, but worse in some areas. I used salicylic acid for a long time to help keep the roughness to a minimum, but the plugs still existed and dug in their proverbial heels, refusing to go away. Even when I could get SOME of them out with those pore strips that promise to yank out all your blackheads, they would return in just a couple of days. (What I'm driving at is that these were more stubborn than your average blackhead. More...Sticky?). I had used Finacea for a while years ago, and loved what it did for my skin, but my insurance copay was almost $200 a tube and I couldn't afford to keep buying it every month. After Azelaic acid finally became available OTC years later I kept a watch out for for a new, affordable Azelaic acid product that would deliver the same results. I tried some products that had unfortunate filler ingredients like dimethicone, in excess. (Yes, I know there are some quality products that contain this ingredient, but as a main ingredient it makes for an unusable product that causes your makeup to ball up on your skin and, for me at least, causes more clogged pores). I was disappointed and disheartened and felt that I was doomed to a life of bad skin unless I was willing to fork over the dough every month for the Finacea. Then I found this product and read the ingredients and saw that there was NO DIMETHICONE and it got my attention. I decided to give it a try, and I'm really glad I did. This serum absorbs quickly into the skin, so much so that I need to use 3-4 drops instead of the 1-2 drops recommended on the bottle because I have trouble spreading it all over before my skin soaks it all up. I leave it on for a few minutes before putting my moisturizer on for max benefit, then apply my makeup like normal. This product doesn't cause my makeup to ball up at all since it absorbs immediately into skin. In the couple of months I've been using it, my skin feels so smooth, and all of those ugly white pore plug slivers are gone. I also have drastically fewer pustules that surface throughout the day from my rosacea. I keep touching my face because I can't believe that MY skin feels this smooth. I wish I had thought to take before-and-after pics to show other people, but I don't need them for myself. The change is drastic enough that I don't need the "before" pics to realize the difference. At first I did find that my skin responded best to this product if I used it only once a day, but after the first few weeks my skin loves it twice a day, and I have even better results. To sum it up, my skin feels and looks better than it has in years, and I'm glad to have found an affordable alternative to the expensive prescription. If it stays this price, I will continue to purchase again and again.
Read on Amazon ↗I have been using this product twice day (Morning and Night) for over a month. Here is a detailed review for those who are interested! ---------------------------- Performance- 1000000/10!!! - This product is absolutely amazing, especially for my Rosacea. It is incredibly hydrating and leaves a glowing shine behind on my skin. The redness has greatly reduced on my skin and altogether feels healthier. HIGHLY RECOMMEND FOR ROSACEA SUFFERERS! - I will note that this product is incredible hydrating for the skin. If you suffer with more dry skin, then this product is sure to help hydrate! If your skin type is more oily, I wouldn't recommend this product. But if you still want to use it, try using a smaller amount on your skin. ------------------- Consistency-8/10 - The serum is very light weight and breathable on my skin. It has a very smooth texture, not too oily and not too wet. It glides seamlessly with just a drop or two. - The only concerns I have are the stickiness and the fact it can harden and crystallize in the bottle. But these are easy fixes! - If you happen to struggle with stickiness, make sure that your face is damp (not wet). Damp skin is easier to penetrate than dry skin, this goes for any product on your skin! Simply mist your face with water or gently pat your face with a wet cloth before using the serum and make sure to rub it evenly across your skin. (When rubbing in any product, start from the center of your face and work your way out to the edges of your face.) - If you're struggling with the product crystallizing, just submerge the bottle in hot water for a few minutes, it will melt the crystals back to its serum form! --------------------- Ingredients- 10/10 - This product is PERFECT for Rosacea sufferers. I have looked through each ingredient in the bottle and did research to see if it is helpful or harmful. So this portion of the review will be in mind for those who suffer with Rosacea and sensitive skin. I've also taken the liberty to provide what the ingredient is and what it does. - Note: You can NOT buy Azeliac Acid above 10% without a prescription from a doctor. If you see any products labeled above 10% Azeliac Acid that is over the counter, it is most likely fake. ~Ingredient overview~ - Aloe Barbadensis Leaf Extract (Aloe Vera Leaf)- Anti-inflammatory, soothing, antioxidant, hydrating. - Azeliac Acid (Dicarboxylic Acid Molecule)- A rosacea sufferer's best friend! Anti-inflammatory, antioxidant, exfoliant, PH stabilizer, reduces pigmentation, antibacterial. - Panthenol (Vitamin B5)- Helps skin barrier, anti-inflammatory, soothing, gentle, reduces redness. - Niacinamide (Vitamin B3)- Helps skin barrier, anti-inflammatory, soothing, reduces redness, decreases sensitivity. - Sodium Hyaluronate (Sodium salt from Hyaluronic Acid)- Soothing, anti-inflammatory, moisturizing, healing properties. - Camellia Sinensis Leaf Extract (Tea leaf oil extract)- Soothing, calms skin, antioxidant, anti-inflammatory, antimicrobial. - Momordica charantia fruit extract (Bitter Melon extract)- Anti-inflammatory, reduces redness, antimicrobial, skin protection. - Sambucus Nigra Extract (Black Elderberry extract)- Soothing, antioxidant, anti-aging. - (The remaining ingredients are simply used to help the consistency of the product or the PH level. It does not improve or worsen rosacea) ------------------------ Value For Money- 10/10 This is a great product, especially for the money value. I still have plenty of product left after using it twice a day, every day, for over a month! ---------------------- All Together- 10/10!!! I HIGHLY recommend this product, especially if you have rosacea and/or dry skin. It's probably my favorite product I have in my skincare routine!
Read on Amazon ↗Would have given a 5 Star, but this product does not go very far. I believe I read that one drop will cover face. No. It won't. My skin drinks this stuff up, and I'm using at least 3 to 4 drops to cover my whole face and neck. It feels great on my skin and has really helped with the inflammation from acne blemishes. I love the way it is not drying out my skin, but leaving it oil free. That T-Zone oil is almost completely gone and no where near as bad as it used to be. I wish this came in a larger portion size. Also, as another reviewer said, I'm not sure my bottle was filled to the top. The bottle is very dark and you can't see through it. The product was safety sealed and inside the manufacturer's box - so, I doubt it was spilled or tampered with in any way.. I have ordered two more of these. I've used the first bottle over the past week and it's half empty. I doubt a whole bottle will last much more than 2 or 3 weeks if you cover your whole face with it. I also cover my neck. I've had some blemishes in my hairline and this serum DOES NOT make my hair or scalp oily. I wish I'd known about Azelaic Acid 2.5 years ago when I first started taking large doses of B12 and developed adult onset acne. Been trying to figure out the problem all this time, since late 2019, to present (March 2022), and finally read that large amounts of B12 can cause acne. Stopped the B12, March 4. Went 3 weeks without any new breakouts, then got a couple of very tiny bumps on my face - NOTHING LIKE BEFORE. I ordered this product and started using it as soon as I got it. No new blemishes and the couple I had developed are almost totally gone. I'll continue to use this - even after my B12 levels get back down to normal - because I love the way it makes my skin feel so oil free. Azelaic acid is good for maintaining healthy skin too. So, I'm a lifetime fan of Azelaic Acid.
Read on Amazon ↗Really enjoy this product! I've repurchased it something like 6x times now. Maybe more. It gets me through at least a month and a half each bottle, and maybe up to 3 months? It's affordable, it feels amazing, it helps soothe your skin, and helps repair and clear up your skin. It absorbs really well. It's one of the few products I use almost every day (unless I'm in a rush, and even then, I tend to use this over the rest of my routine.) I'm not sure if it's "brightened" my skin, but it's definitely helped with the moisture and keeping my skin clear. I have *extremely* sensitive, dry skin, and this was one of the few products that doesn't irritate and works! I love that it's combined with hyaluronic acid, but it also absorbs into my skin quickly. I typically use it twice a day - morning, and after washing my face at night (if I'm not being too lazy.) I definitely used this in my soothing process after starting tretinoin just over a year ago. I think I started this before tret, to be honest, and it was one of the few (of SEVERAL) products that I kept in my skin care process. I like using it on my face and neck, but I have also rubbed it onto my shoulders, hands, arms, and elbows, to help keep them soft and moisturized. I generally use just under one dropper of it every time I use it and put it mainly on my face and neck, but there's usually enough left on my hands that I can rub it into my elbows and shoulders and still benefit from it. Like I said, this is a regular repurchase for me. I always make sure to have more in my "stock" whenever I notice I'm running low, because I love this and don't want to go without. It's my first step after washing my face. Sometimes I'll put more stuff on after, but this on its own is enough when you're not damaging your skin barrier. Esp outside of winter. (Winter and tret mean I have to use this stuff like 2x/day, but that's fine!) I've been so happy with this, I haven't even considered trying another brand of azelaic acid. Cos de Baha has great products, in my experience. Enjoy!
Read on Amazon ↗Okay so I actually bought this as a hail-mary after being told by my dermatologist that the only way to get rid of the PIE (that I've had for years) and the other dark spots is by paying a minimum of $380 or $700-smth for a SINGLE treatment, and I was obviously like SUPER against that cuz nobody in this day and age can willingly pay that much for smth like this, so I started doing a bit of research and found Azelaic acid was a good idea, so I bought this Umm so like it's almost creepy how well this works?? Like I'm kind of pissed that this existed the entire time, and I even put my bf onto this like last year (I forgot this product existed 😢) to go w/ his tretinoin treatment, but I never thought to try it myself even though it gave him crazy results 💔 Like it's actually insane. It soothed SO much irritation, worked great with my routine, feels nice under moisturiser, zero fragrance, and omg dude my skin is so happy with this on it's actually insane I apply it at night after using my toners and before my moisturiser. That is it. Did it four nights in a row and randomly everything's just BAM. GONE. Even the texture is annihilated too like omg bro this is insane Like I don't think y'all can understand how like amazed and confused I am but like I mean it works and it works WELL. Good Lord bro I'm writing this review like 3/4 weeks after my first use btw and the results have basically stayed the same w/ some more lightening of the darkest spots. Genuinely insane but like I said ts REALLY works😰
Read on Amazon ↗Reviews are from verified Amazon customers, shown for reference. We don't edit or endorse individual reviews.
Cos De BAHA Azelaic Acid 10% Serum with Niacinamide: frequently asked questions
What is Cos De BAHA Azelaic Acid 10% Serum with Niacinamide?
This is a dual-active serum that combines 10% azelaic acid with niacinamide in a single lightweight formula. Azelaic acid works to even skin tone and reduce the appearance of blemishes, while niacinamide helps minimize pores and control excess oil. It targets acne, dark spots, and uneven texture in one step.
Does Cos De BAHA Azelaic Acid 10% Serum contain niacinamide?
Yes — niacinamide is a key ingredient in this serum alongside 10% azelaic acid. The combination makes it a convenient option if you want both actives without layering two separate products. It's one of the more straightforward ways to get this pairing at an accessible concentration.
Who is this serum best suited for?
It's a good fit for oily or acne-prone skin types dealing with post-breakout dark spots or uneven tone. The niacinamide component helps regulate sebum and tighten the look of pores. Those with sensitive skin should patch test first, as 10% azelaic acid can cause mild tingling or redness during initial use.
Can I use niacinamide and azelaic acid together in the same routine?
Yes, niacinamide and azelaic acid are well-tolerated together and address complementary concerns — azelaic acid targets discoloration and blemishes while niacinamide calms and refines pores. This serum combines both, so there's no need to worry about layering order or ingredient conflict. It's one reason this formula appeals to those simplifying their routines.
How often should I use Cos De BAHA Azelaic Acid 10% Serum?
Start with once daily — either morning or evening — and see how your skin responds. If well tolerated after one to two weeks, you can use it twice daily. Apply to clean, dry skin before moisturizer. If irritation occurs, reduce frequency and build up gradually. Consistent use over several weeks is typically needed to see noticeable improvement in dark spots.
Which concerns does this serum actually address?
The formula targets three main concerns: acne and active breakouts, post-acne dark spots and hyperpigmentation, and oily skin with enlarged-looking pores. Azelaic acid is the primary driver for tone-evening and blemish reduction, while niacinamide supports oil control and overall skin texture refinement.
How does this compare to serums with just one of these actives?
Single-active serums give you more flexibility to adjust concentrations independently, but this serum's value is convenience — both actives in one step. If you're also looking for brightening via vitamin C, that's a different mechanism; something like TruSkin Vitamin C Serum with Hyaluronic Acid & Vitamin E would complement rather than overlap with this routine.
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