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Tranexamic Acid 10% Serum

HyperpigmentationSerum

Tranexamic Acid 10% Serum — Reddit Reviews

by Cos De BAHA

81nextscore55 verdicts

Updated October 17, 2026

Redditors report faster dark-spot fading; studies found niacinamide's acne results uncertain.

What the community says

Backed by 72 studies

This is a 10% tranexamic-acid serum with 2% niacinamide, aimed at stubborn post-acne marks and uneven pigmentation. Redditors report visible fading, while studies found topical niacinamide's acne results uncertain; the sticky aloe-like finish and occasional severe irritation are real drawbacks.

From Reddit

Backed by 28 threads from r/SkincareAddiction, r/tretinoin and 5 more.

Read the threads ↓

What people love

  • 10% tranexamic acid for post-acne pigmentation
  • Visible fading reported within one to three months
  • Layers under SPF and makeup without pilling

Watch out for

  • Sticky aloe-like texture can pill and feel congested
  • Severe barrier reactions reported: stinging, bleeding, damaged skin
  • Results vary; some users saw no progress

Product details

Where to buy

What the science says vs. what Reddit says

  • Hyperpigmentation

    Some evidence

    Tranexamic Acid: 9 studies tested it on its own. See all 19 studies

    On Reddit: Injury scars can fade markedly: one user reports a facial scar nearly gone after three months of serum use. 25 mentions

    Both ingredients for hyperpigmentation

    Tranexamic Acid Some evidence

    • Most studies found it helped fade dark patches, especially in melasma
    • It often worked about as well as other common dark-spot treatments
    • Using it with other treatments often faded patches more than the other treatment alone
    • Some studies found injected tranexamic acid, microneedling, or oral use worked better than other ways of using it
    • The most common side effects were stomach upset, skin irritation, and menstrual changes

    Studied at 2–5%this product: 10%

    Niacinamide Some evidence

    4 studies tested it on its own. See all 17 studies

    • All 4 studies that tested it on its own found it helped fade dark spots
    • It reduced facial dark spots better than a moisturizer without niacinamide
    • Some studies found skin looked lighter as dark spots faded
    • When used with salicylic acid, it improved dark patches more than salicylic acid alone
  • Acne

    Some evidence

    Niacinamide: 6 studies tested it on its own. See all 17 studies

    What the studies found
    • Most studies found niacinamide helped acne
    • It often cleared acne about as well as clindamycin when put on the skin
    • Some studies found it helped reduce red, sore spots and pimples
    • Some evidence is still uncertain because some studies found no clear difference
  • Anti-Aging

    Some evidence

    Niacinamide: 2 studies tested it on its own. See all 8 studies

    What the studies found
    • Both studies that tested it on its own found it helped with signs of aging
    • It improved how firm and elastic the skin looked
    • It reduced wrinkles and uneven tone, including spots, redness, and yellowing
    • It helped the skin hold more water and reduced water loss through the skin
  • Skin Barrier

    Not proven yet

    Few or mixed studies. This claim isn't established.

    Niacinamide: 1 study tested it on its own. See all 17 studies

    What the studies found
    • The one study that tested it on its own found it helped the skin barrier
    • It lowered water loss through the skin
    • It increased the thickness of the outer skin layer
  • Redness/Irritation

    Not proven yet

    Few or mixed studies. This claim isn't established.

    Centella/Cica: 1 study tested it on its own. See all 2 studies

    On Reddit: Aloe-like slip feels soothing on redness, acne, and eczema, and layers under SPF or makeup. 5 mentions

    What the studies found
    • The one study that tested it on its own found it helped redness and irritation
    • It reduced redness more than a placebo after laser treatment
    • It also improved crusting and overall skin appearance

Research context, not treatment advice. Studies are about the ingredient, not necessarily this exact product.

Real Reddit threads — 81 mentions across 28 threads

Cos De BAHA Tranexamic Acid 10% Serum on Reddit, in one place — 28 threads from r/SkincareAddiction, r/tretinoin and 5 more, summarized.

“Cos de Baha Tranexamic Acid serum (tranexamic + niacinamide) is one of the generic options I would suggest”

Mentioned

“and can certainly be used with retinoids comfortably.”

Mentioned

“Ideally ... you would cleanse, apply the cos de baha tranexamic serum, moisturize on damp skin.”

Mentioned

“I'm trying out the cos de baha AZ20 with 20% azelaic acid.”

Mentioned

“Think it's going well so far, but I've only started introducing it two weeks ago”

Mentioned

“- cos de baha AZ15.”

Positive

“- cos de baha Az15.”

Positive

“My full routine is:”

Positive

“The serum is so soothing for my redness/acne/eczema and truly feels hydrating too, it kinda has an aloe vera like slip when applied and works well under my SPF/makeup.”

Positive

“Cos de Baha: been using this now for two weeks since I came back from my trip. It has a nice slip to it when put on damp skin, sinks in quickly without leaving tacky feel, and I have noticed that my skin texture looks smoother and pores appear smaller.”

Positive

“can you plss give reviews for cos de baha az serum”

Positive

“when their prices started climbing, I personally switched to Cos de Baha and have been very pleased with their niacinamide and TXA serums.”

Positive

“- Cos de Baha (serums),”

Positive

“For people into K- or Asian beauty, here are few brands I've personally used and liked:”

Positive

“I love the Cos de Baha Azalaic acid serum”

Positive

“comes in 5% and 10%.”

Positive

“I see immediate results in soothing redness.”

Positive

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