Kojic acid or alpha arbutin: which is better for dark spots?
Short answer: Both slow down tyrosinase, the enzyme your skin uses to make pigment, so both can help even out tone over 8 to 12 weeks. Alpha arbutin tends to be gentler and suits sensitive skin. Kojic acid can work well but is more likely to sting or cause a rash. Many serums combine low amounts of both.
Key takeaways
- Same goal, slightly different strengths.
- Sensitive or reactive skin: start with alpha arbutin.
- Patch test kojic acid first. Stop if it itches or burns.
- Neither works without daily sunscreen.
How do they work?
Kojic acid comes from fungi used in fermenting rice. Alpha arbutin is a lab-made form of arbutin, a compound found in bearberry leaves. It is related to hydroquinone but much milder. Both reduce the activity of tyrosinase, so less new pigment forms. Neither removes pigment that is already there overnight. The skin has to renew itself, which takes weeks.
Kojic acid vs alpha arbutin at a glance
| Kojic acid | Alpha arbutin | |
|---|---|---|
| How it works | Slows tyrosinase | Slows tyrosinase |
| Gentleness | Can sting or cause a rash in some people | Usually well tolerated |
| Common amounts | About 1 to 2% | About 1 to 2% |
| Best for | Normal or oily skin that handles actives | Sensitive skin, first-time users |
Can you use them together?
Yes. Many serums pair them at low amounts so each one can do its job without high, irritating levels. If you use a combined serum, skip other strong actives at the same time.
How do you start?
- Patch test on the side of your neck for 2 to 3 days.
- Apply a few drops on clean, dry skin at night, every other day for the first 2 weeks.
- Follow with moisturizer.
- Wear sunscreen every morning.
- Judge results at 8 to 12 weeks, not before.
Used in this routine
The Asaya 2% Kojic Acid + 1% Alpha Arbutin Face Serum combines both. You can add it to the routine in our Even Tone Set.
FAQ
Is alpha arbutin the same as hydroquinone?
No. It is related, but much gentler, and it is sold over the counter in cosmetics.
Can I use these with vitamin C?
Many people do, morning vitamin C and night kojic or arbutin. Add one product at a time so you know what your skin reacts to.
Sources
- Hyperpigmentation therapy: a review (Journal of Clinical and Aesthetic Dermatology)
- Comparative study on depigmenting agents in skin of color
- American Academy of Dermatology: How to fade dark spots in darker skin tones
General information, not medical advice. Patch test new products on a small area first. If a spot changes shape, color or size, or a product burns, see a board-certified dermatologist.
This article is general information, not medical advice. See a dermatologist for skin conditions.