Niacinamide serum: benefits, dosage and how to use it

In short: niacinamide (vitamin B3) helps mattify, refine the look of pores, even out skin tone and support the skin barrier. A 2 to 5% dosage suits most skin types, 10% suits skin that is used to it. It mixes with almost every active.

Visible pores, shine by midday, uneven skin tone: niacinamide (نياسيناميد) has become the favourite active of combination to oily skin, and one of the most searched for in Morocco (“sérum B3”, “sérum mela B3”). Here is everything you need to know: benefits, dosage, side effects, combinations and brands.

What is niacinamide?

It is the form of vitamin B3 used in cosmetics. Unlike niacin, it rarely causes flushing. It is stable, well tolerated and compatible with most routines.

The benefits of niacinamide for the skin

Supports the skin barrier: helps the skin retain water better.
Soothes the look of redness.
Refines the look of pores by regulating the look of sebum.
Mattifies the T-zone.
Helps even out skin tone and fade the look of dark spots.
Improves the look of fine lines with regular use.

These benefits are described by medical sources such as Cleveland Clinic and WebMD.

Can pores really “shrink”?

Pore size depends largely on genetics. No treatment closes them. However, less oily, well-exfoliated and hydrated skin makes pores visually less noticeable: that is the realistic effect of a niacinamide serum combined with gentle exfoliation.

Which dosage to choose: 2%, 5% or 10%?

2 to 5%: well tolerated by most skin types, ideal to start. Our niacinamide serum is at 5%, with zinc PCA, witch hazel and panthenol.
10%: a popular dose (The Ordinary, Paula’s Choice, Anua), but with a risk of tingling and breakouts for some skin types.
Beyond that: little clear additional benefit, more discomfort.

Comparison: niacinamide across brands

The Ordinary: Niacinamide 10% + Zinc 1%, the affordable benchmark.
Paula’s Choice: niacinamide 10% booster, aimed at combination to oily skin.
Anua: niacinamide 10% serum with tranexamic acid, popular in K-beauty.
COSRX: The Niacinamide 15, a concentrated K-beauty formula.
La Roche-Posay: Mela B3 serum, designed for the look of dark spots (a name that often comes up in Moroccan searches).
Moroccan brands and parapharmacies: several B3 serums at very varied prices.
Cosmogenesis Labs: 5% niacinamide, zinc PCA, witch hazel, panthenol, 30 ml, vegan.

How to use a niacinamide serum

Cleanse the face.
Apply 3 to 4 drops over the whole T-zone and the cheeks.
Let it absorb, then apply a light cream.
In the morning, finish with SPF 50.

Morning, evening or both. If you are just starting, one application a day is enough.

What should it be paired with?

Vitamin C: compatible (vitamin C serum guide).
AHA and BHA: an effective duo for clogged pores (AHA and BHA guide).
Retinol: niacinamide helps limit discomfort (retinol guide).
Hyaluronic acid: to avoid dehydrating oily skin.

Possible side effects

Redness, tingling or small breakouts can appear at high doses or on very sensitive skin. Start low, patch test in the crook of the elbow, and space out applications in case of discomfort.

Niacinamide, blemishes and the habits that count

Cleanse morning and evening, without rubbing.
Do not squeeze blackheads.
Apply a fluid SPF 50.
Remove make-up every evening.

Niacinamide is part of routines for blemish-prone skin, but it does not replace medical treatment. For a complete routine, see our oily skin routine guide and the refined pores routine.

Niacinamide and oily skin: what do studies say?

Niacinamide is one of the few cosmetic actives studied on sebum. In a trial published in 2006 (Draelos et al.), 2% niacinamide applied to the face reduced the sebum excretion rate after two to four weeks in Japanese volunteers, and surface sebum in Caucasian volunteers after six weeks. Another study (Bissett et al., 2005), using 5% niacinamide for twelve weeks, observed an improvement in the appearance of fine lines, spots, redness and elasticity.

These trials involve small groups and specific formulas: they show a trend, not a promise. They do explain why dermatologists often mention niacinamide for combination to oily skin.

Niacinamide serum or cream?

Serum: fluid texture, targeted concentration, it slips under any cream. It is the simplest format for oily skin that dislikes thick layers.
Cream: more comfortable for combination skin that feels tight on the cheeks. It often contains less niacinamide.
The duo: a niacinamide serum under a light cream is enough in the vast majority of routines. There is no need to stack three niacinamide products.

Morning or evening? A sample week

Niacinamide does not make the skin sensitive to the sun: it can be used morning and evening. For oily skin, here is a simple rhythm:

Every morning: gentle cleanser, niacinamide serum, light cream, SPF 50.
Two to three evenings a week: the AHA + BHA exfoliating toner, then a cream.
The other evenings: niacinamide serum again, or a hyaluronic acid hydrating serum if the skin feels tight.

Niacinamide and post-blemish marks on olive skin

On olive skin, common in Morocco, a blemish often leaves a brown mark that lasts several weeks: this is post-inflammatory hyperpigmentation. Niacinamide is among the actives studied to fade the look of these marks, alongside vitamin C and retinoids, according to a systematic review published in 2024 on darker skin. Sun protection remains the basic step, because the sun darkens these marks. See our guide dark spots: morning and evening routine.

Reading the label of a niacinamide serum

The INCI name: “Niacinamide”. The higher it is in the list, the more concentrated it is.
The percentage: serious brands state it. 4 to 5% covers most needs.
The partners: zinc PCA (look of sebum), panthenol (comfort), hyaluronic acid (hydration).
The bottle: niacinamide is stable, a standard dropper bottle is enough.
The origin: choose a properly labelled product, with an identified company responsible for placing it on the market and a readable expiry date.

What niacinamide does not do

It does not replace an exfoliant for established blackheads, nor a medical treatment for inflammatory acne. It does not “close” pores and does not remove sebum, which protects the skin. It helps improve its appearance, with regular use. To compare with other actives, browse all our face serums.

Sources and further reading

Informational content that does not replace the advice of a healthcare professional. If in doubt, for reactive skin, during pregnancy or for a dark spot that changes, consult a dermatologist.

Frequently asked questions

What does niacinamide do?

It helps mattify, refine the look of pores, even out skin tone and support the skin barrier.

Which percentage of niacinamide should you choose?

2 to 5% to start. 10% for skin that is used to it. Beyond that, the risk of discomfort increases.

Is niacinamide suitable for sensitive skin?

Yes at a low dose, after a patch test in the crook of the elbow.

Can niacinamide and vitamin C be mixed?

Yes, the two are compatible.

How long does it take to see an effect?

Shine often decreases within two to four weeks. Pores and skin tone take up to eight weeks.

Do you need SPF with niacinamide?

Yes, SPF 50 in the morning: niacinamide does not protect from the sun.

Does niacinamide cause purging?

No. Purging mainly happens with exfoliants and retinoids, which speed up skin renewal. Breakouts after niacinamide are more likely a sign of irritation: lower the frequency or the concentration.

Niacinamide or salicylic acid for oily skin?

They work well together: niacinamide helps mattify and even out the complexion, salicylic acid (BHA) unclogs pores. Niacinamide can be used every day and BHA two to three evenings a week.

Can a niacinamide cream and a niacinamide serum be used at the same time?

It is possible, but rarely useful. A 4 or 5% serum under a light cream is enough in most routines.

Niacinamide serum: visible pores and oily skin, how to use it