Can you use glycolic acid (AHA) with niacinamide?
Yes. AHAs such as glycolic, lactic and mandelic acid can share a routine with niacinamide; the idea that the acid turns niacinamide into flush-causing niacin on your skin isn't supported.
Why
Niacinamide can slowly change into niacin in acidic, warm conditions, but at room temperature this takes weeks to months, so it matters for products stored together rather than for layering. A randomized study of a serum containing both niacinamide and glycolic acid (with other actives) found it well tolerated over several months. The part to watch is the AHA itself, which can cause stinging and dryness and makes skin more sensitive to the sun.
How to use them
Use them together in either order, or at different times if your skin feels tight or stings. Keep AHAs in your evening routine and use broad-spectrum sunscreen the next morning.
Sources
- 1Can you use Niacinamide and Vitamin C (Ascorbic Acid) together? · KindofStephen, 2016
- 2Evaluation of the Efficacy of a Serum Containing Niacinamide, Tranexamic Acid, Vitamin C, and Hydroxy Acid Compared to 4% Hydroquinone in the Management of Melasma · Journal of Cosmetic Dermatology, 2025
- 3Alpha Hydroxy Acids · U.S. Food and Drug Administration, 2022
General cosmetic information, not medical advice. Written with AI assistance from the sources above; updated October 2026.