Can You Use Peptides and Niacinamide Together?

Peptides and niacinamide can be used together, including in the same serum or moisturizer, and the two ingredients appear together in studied formulas.¹ You don't need two separate serums to use them. A peptide serum under a niacinamide moisturizer gives each ingredient a place in your routine, and so does one formula containing peptides and niacinamide, so the right setup depends mostly on what your current products already contain.

What each ingredient does

Niacinamide is a form of vitamin B3.³ It helps skin produce lipids, including ceramides, that limit water loss through its outer layer, a bit like mortar filling the gaps in a brick wall. In research on dry skin, topical niacinamide increased ceramide and fatty-acid levels and reduced the amount of water escaping through the skin, which is one way it supports the moisture barrier.²

Niacinamide can also improve the appearance of uneven tone and fine lines. In one study, a niacinamide formula improved the appearance of dark spots, fine lines and wrinkles compared with the same base formula without niacinamide.³ If you're using a peptide treatment for fine lines, uneven tone may be another concern you'd like niacinamide to help with.

Peptides are short chains of amino acids, with different uses in skincare. One peptide studied for wrinkles is a palmitoyl pentapeptide known as pal-KTTKS, developed to encourage production of collagen, a protein that helps support skin. In a trial, a moisturizer containing pal-KTTKS improved fine lines and wrinkles more than the same moisturizer without it.⁴ The skincare peptide reference explains individual peptide names and their research.

So their benefits overlap, since both niacinamide and pal-KTTKS have been studied for fine lines and wrinkles, and niacinamide adds its tone and barrier benefits on top. That makes the pairing worth considering when you want to work on fine lines, tone and the moisture barrier at once.^{3, 4}

What has been studied together?

One small study tested a serum containing niacinamide, a peptide, hyaluronic acid and other ingredients. Participants applied it to one side of their forehead and followed their usual moisturizing routine on the other. At four weeks, the serum-treated side had higher hydration.¹

The researchers also measured water loss through the skin. Hydration describes how much water is in the outer layer, and water loss shows how well the barrier keeps it from escaping, a bit like the difference between how full a bucket is and how fast it leaks. Although the serum-treated skin was more hydrated, water loss didn't differ significantly between the two sides.¹

Because the researchers compared the complete serum with a usual moisturizing routine, the result applies to the formula as a whole. The ingredients' individual contributions weren't tested separately.¹ So the study tells you the combination can work in one serum, not how much niacinamide or the peptide added on its own.

How to fit the pair into your routine

Start with the products you already like, and build from there.

If you already use niacinamide: you can keep your niacinamide product when you introduce a peptide treatment. A peptide serum can go on before your niacinamide moisturizer, or, if your niacinamide is a serum, you can follow it with a peptide-containing moisturizer. Either way, the serum goes before the moisturizer, with any product-specific directions guiding application.⁵

If you already use a peptide serum: a moisturizer containing niacinamide can go over it, especially if you're ready to replace your moisturizer anyway. A separate niacinamide serum is also an option if there's a formula you prefer. Before adding a niacinamide serum, check whether your peptide serum or moisturizer already contains niacinamide.

If one product already contains both ingredients: you're already using the combination. An extra serum is optional. You might still prefer a separate product, but you don't need one just to use peptides and niacinamide together.

If you choose two treatment serums, apply them after cleansing and before moisturizer, following any product-specific directions. The guide to choosing and using a peptide serum covers its place in a broader routine.⁵

If both products are new, introduce one at a time. Test a new product on a small area before wider use, and stop using a cosmetic product that causes burning, itching, or a rash. Adding them separately makes it easier to tell which product your skin is reacting to.⁶

Before you buy anything, read the ingredient lists on the serum and moisturizer you already use. You may find the pair is already in your routine.

Sources

1. Rusic D, et al. Pilot Study on the Effects of a Cosmetic Serum Containing Niacinamide, Postbiotics and Peptides on Facial Skin in Healthy Participants: A Randomized Controlled Trial. Life, 2024.
2. Tanno O, et al. Nicotinamide increases biosynthesis of ceramides as well as other stratum corneum lipids to improve the epidermal permeability barrier. British Journal of Dermatology, 2000.
3. Bissett DL, et al. Niacinamide: A B vitamin that improves aging facial skin appearance. Dermatologic Surgery, 2005.
4. Robinson LR, et al. Topical palmitoyl pentapeptide provides improvement in photoaged human facial skin. International Journal of Cosmetic Science, 2005.
5. American Academy of Dermatology. Should I apply my skin care products in a certain order?
6. American Academy of Dermatology. How to maximize results from anti-aging skin care products.