Can you use niacinamide with mandelic acid?
The chemistry
Mandelic acid is an alpha hydroxy acid with a large molecule that penetrates slowly, making it gentler than glycolic acid; clinic peel studies show it helps acne and post-acne pigmentation (Dayal 2020, Garg 2009). Niacinamide reduces redness, oil and blotchiness and strengthens the barrier (Bissett 2005, Tanno 2000). Mandelic acid handles exfoliation and clogged pores, niacinamide calms and evens tone. Neither inactivates the other, and the myth that niacinamide and acids should never meet comes from outdated high-heat lab conditions. For darker skin prone to post-inflammatory marks, both are popular because they are less likely to cause the irritation that leads to new pigment.
Fit
Gentle exfoliation plus calming barrier support.
Who
Acne-prone, sensitive or darker skin with marks.
Sun
Mandelic acid raises sun sensitivity.
Common mistakes
Use mandelic acid at night two to four times a week and niacinamide daily. Products at 5 to 10 percent mandelic acid are typical for home use. If you also use a retinoid, keep mandelic acid on separate nights. Results for texture appear within a few weeks; pigment takes longer. Do not expect a home mandelic serum to equal a clinic peel. Many combination serums sold for acne-prone skin pair mandelic acid with niacinamide at modest strengths, which is convenient. If you use separate products, apply the mandelic acid first on dry skin, then niacinamide. Watch for redness lasting more than an hour after application; that suggests the acid strength or frequency is too high. Mandelic acid was originally derived from bitter almonds, but cosmetic grades are synthetic, and almond allergy is not a known reason to avoid it, though a patch test is reasonable if you are anxious.
Your routine
Morning
- Cleanser
- Niacinamide serum
- Sunscreen SPF 30+
Evening
- Cleanser
- Mandelic acid (some nights)
- Niacinamide moisturizer
Go slower if
AHAs increase sun sensitivity (Kaidbey 2003). Avoid on broken or sunburned skin.
Evidence strength
Moderate for niacinamide; moderate for mandelic acid from peel studies. No direct combination trial.
Products with niacinamide or mandelic acid
The Ordinary Niacinamide 10% + Zinc 1%
Picked for niacinamide
10% niacinamide with 1% zinc PCA in a short formula.
Buy on Amazon (opens in a new tab)The Ordinary Mandelic Acid 10% + HA
Picked for mandelic acid
Mandelic acid with glycerin and hyaluronic acid crosspolymer, fragrance-free.
Buy on Amazon (opens in a new tab)FAQ
Is mandelic acid better than salicylic acid for me?
Peel studies found them comparable for acne; mandelic suits sensitive skin, salicylic oily skin (Dayal 2020).
Can I use both every night?
Mandelic acid every night is often too much; start with a few nights.
Will this help enlarged pores?
Exfoliation and oil control can make pores look smaller.
Can mandelic acid and niacinamide help fungal acne?
Fungal acne (Malassezia folliculitis) usually needs antifungal treatment; these ingredients are not a substitute, so see a doctor if bumps are itchy and uniform.
Related combinations
- RetinolYes
- Vitamin CYes
- TretinoinYes
- Salicylic AcidYes
- Hyaluronic AcidYes
- Glycolic AcidYes
- Benzoyl PeroxideYes
- SunscreenYes
Sources
- Dayal S, Kalra KD, Sahu P. Comparative study of efficacy and safety of 45% mandelic acid versus 30% salicylic acid peels in mild-to-moderate acne vulgaris. J Cosmet Dermatol. 2020;19(2):393-399.
- Garg VK, Sinha S, Sarkar R. Glycolic acid peels versus salicylic-mandelic acid peels in active acne vulgaris and post-acne scarring and hyperpigmentation: a comparative study. Dermatol Surg. 2009;35(1):59-65.
- Bissett DL, et al. Niacinamide: a B vitamin that improves aging facial skin appearance. Dermatol Surg. 2005;31(7 Pt 2):860-865.
- Tanno O, Ota Y, Kitamura N, Katsube T, Inoue S. Nicotinamide increases biosynthesis of ceramides as well as other stratum corneum lipids to improve the epidermal permeability barrier. Br J Dermatol. 2000;143(3):524-531.
- Kaidbey K, et al. Topical glycolic acid enhances photodamage by ultraviolet light. Photodermatol Photoimmunol Photomed. 2003;19(1):21-27.