It wasn’t long ago that tranexamic acid was the reserve of medicine. Wielded by doctors for its blood clotting properties, it was found effective at halting hemorrhages, and is still used as an intervention in bleeding symptoms today. But a fortuitous mistake ushered the ingredient into mainstream skincare when a patient prescribed oral tranexamic acid experienced skin lightening as a side effect.

Now, tranexamic acid (also denoted by TXA) can be found over the counter and almost everywhere you look. As a beauty editor with skin prone to hyperpigmentation, tranexamic acid serums have been a saving grace. To find out how tranexamic acid works so well, I asked experts for a full breakdown. Ahead, you’ll find everything you need to know about the ingredient, from the ideal concentration to all the best tranexamic acid products to use.

• Debbie Thomas is a skin and laser expert, VIP facialist and the founder of Clinic.
• Dr Tatyana Lapa-Wright is an aesthetic doctor and the owner of Hardwick Clinic.

What is tranexamic acid?

“Tranexamic acid is a synthetic derivative of the amino acid lysine,” Dr. Lapa-Wright informs Vogue. It’s not an acid in the conventional sense—it does not have exfoliating properties. But it does have brightening benefits on the skin. According to Thomas, tranexamic acid is used topically for treating pigmentation and inflammatory redness. “It effectively reduces excess melanin production without bleaching or stripping the skin and is ideal for melasma, post-inflammatory pigmentation, and redness-prone skin.”

How does tranexamic acid work on skin?

Oral tranexamic acid is a controlled medicine, typically prescribed to help with menstrual symptoms or nosebleeds, though some dermatologists may prescribe the pills for melasma patients. Whether oral or topical, TXA works by inhibiting tyrosinase (an enzyme that triggers pigment production) to reduce the appearance of dark patches. Studies have shown that tranexamic acid can also reduce inflammation, which makes it helpful in the prevention and reduction of post-inflammatory hyperpigmentation (PIH). Both of our experts add that TXA strengthens the skin barrier, evens skin tone, and can soothe redness when used as part of a dedicated routine.

How to use tranexamic acid for hyperpigmentation:

“Apply tranexamic acid once daily (evening preferred), after cleansing and before moisturizer,” Thomas instructs. “Avoid layering with strong acids or retinoids initially—use it on its own for two to three weeks before introducing other actives.” Per Dr. Lapa-Wright, beginners should start low and go slow, as TXA can be irritating on sensitive skin. And don’t skip the sun protection, which Thomas says will protect your results: “Use a broad spectrum SPF, and if it is tinted, even better.“

How long does it take for tranexamic acid to work?

Timelines given by our experts vary, but both agree that tranexamic acid offers “gradual results, not overnight miracles.” On average, you can expect to notice visible improvements in 8 to 16 weeks with consistent use.

What to look for in an effective tranexamic acid formula

• Optimal concentration: According to Thomas, effective tranexamic acid formulas will have TXA listed within the top half of the ingredients list, ideally at a 2 to 5% concentration. “Higher isn’t always better,” Dr. Lapa-Wright notes.
• Additional ingredients: Both experts recommend looking for TXA paired with complementary actives such as niacinamide, azelaic acid, and liquorice root, which safely enhance its effects. “Avoid irritants like alcohol and fragrances, especially for sensitive skin.”
• Protective packaging: Per Thomas, look for airtight, opaque packaging that protects ingredient stability.

Now you know what to look for and how best to introduce tranexamic acid into your skincare routine, you can try using the ingredient to get closer to your clear skin goals.