Compare · Ingredients

Niacinamide vs Sulfur

Niacinamide: Supports barrier function, uneven tone and oiliness. Sulfur: Used in some acne products and prescribed or compounded scabies regimens.

Research updated 2026-10-25

Six niacinamide products on white, including The Ordinary 10% + Zinc 1%, Paula's Choice Booster and EltaMD UV Clear

Four sulfur acne products: Kate Somerville EradiKate, De La Cruz 10% sulfur ointment, The Ordinary and Thayers

Which one?At a glance What it helps Diagrams Using both Strengths Results Safety How it works Products Questions

Which one is right for you?

Choose Niacinamide if…

Choose for barrier support, uneven tone and oiliness; often the gentler starting point.

Barrier support or sensitive skin
Uneven tone or oiliness
You want a gentle, stable starting point

Choose Sulfur if…

Consider for an appropriate acne product; suspected scabies needs diagnosis and a complete plan.

Mild acne or a spot treatment
Sensitive skin that dislikes benzoyl peroxide
Smell is acceptable

Fine together

Can you use both?

Niacinamide can calm skin alongside sulfur acne treatments.

At a glance

● Niacinamide

● Sulfur

Type

Vitamin B3 (nicotinamide)

Keratolytic and antimicrobial medicine

What it does

Supports the barrier and improves uneven tone

Used in some acne products and prescribed or compounded scabies regimens.

Best for

Barrier support; uneven tone; oiliness

Acne; Scabies

Studied concentrations

2–5%

Acne products commonly use 3–10%; scabies ointments use separate 5–10% regimens.

When to use

Morning or night

Morning or night, as directed by the finished product.

Time to results

About 4–12 weeks, depending on the concern

Often 8–12 weeks in small cosmetic studies; results may be subtle

Irritation

Usually low; stinging or redness can occur

Odour, dryness and irritation can limit use; avoid strong products on inflamed eczema.

Sensitive skin

Often suitable in a gentle formula

Choose a simple formula and test a small area first. Individual tolerance matters more than an ingredient’s reputation for being gentle.

Available

Over the counter

Prescription or cosmetic status depends on the active, formula and country; check the label.

What it helps

Compare uses by strength of evidence. Evidence level describes confidence in a benefit, not its size.

Evidence level

Niacinamide

Sulfur

Moderate evidenceSome supportive research

a very close view of irritated dry skin with fine flaking and no identifiable body part on light skin.

Barrier Support

Supports barrier lipids and helps reduce water loss in dry skin.

A relaxed forehead with faint shallow horizontal fine lines.

Wrinkles and Fine Lines

A small controlled trial of 5% niacinamide found modest improvement in fine lines.

Uneven Skin Tone.

Uneven Skin Tone

Can improve uneven pigmentation with regular use and sun protection.

Oiliness.

Oiliness

2% niacinamide improved some measures of facial oiliness in controlled studies.

The finger webs and wrist on fair light skin, with small red bumps, several thin gray burrow lines a few millimetres long, and scratch marks across the area.

Scabies

CDC lists compounded 5–10% sulfur ointment as an alternative treatment.

Limited evidenceEarly or small studies

Inflamed acne on light skin. The spots sit in a patch of pink, and the ring of redness around each one is easy to see. A few have a yellow-white head, and the skin between them is dry and flaking.

Acne

Small trials suggest benefit for inflammatory acne; consider it a supporting option.

Flat tan patches with soft irregular edges across the forehead and upper cheek of an adult with light skin, the surface completely smooth.

Melasma

A small trial of 4% niacinamide found improvement alongside sunscreen.

Redness and fine superficial vessels across a light-skinned cheek and nose.

Rosacea

A niacinamide moisturizer was studied for barrier support; its other ingredients also matter.

Inflamed acne on light skin. The spots sit in a patch of pink, and the ring of redness around each one is easy to see. A few have a yellow-white head, and the skin between them is dry and flaking.

Acne

Used in acne products, with less robust modern evidence than standard acne medicines.

Insufficient evidence

Enlarged Pores on light skin.

Enlarged Pores

Less oil may make pores less noticeable; lasting pore-size reduction is unproven.

Extreme close-up of light skin in an active eczema flare, too close to tell which part of the body it is. Blotchy pink-red inflammation covers the whole frame with no clear edge, with small raised bumps, fine dry scale and a few fresh scratch marks.

Eczema

Barrier benefits do not establish niacinamide as an eczema treatment.

A relaxed forehead with pronounced deep horizontal furrows.

Deep Wrinkles

Fine-line improvement does not establish correction of deep folds.

Redness and fine superficial vessels across a light-skinned cheek and nose.

Rosacea

Combination sulfacetamide/sulfur products do not establish sulfur alone as treatment.

Extreme close-up of light skin in an active eczema flare, too close to tell which part of the body it is. Blotchy pink-red inflammation covers the whole frame with no clear edge, with small raised bumps, fine dry scale and a few fresh scratch marks.

Eczema

The reviewed sources do not establish this ingredient as a treatment for this concern.

Salmon-pink patches with fine greasy yellowish scale in the crease beside the nose and through the eyebrow on fair skin, with soft edges that fade into normal skin.

Seborrheic Dermatitis

The reviewed sources do not establish this ingredient as a treatment for this concern.

Acne scarring on light skin. Small sharply cut pits and broad shallow dips across a cheek, several sitting inside faint flat pink marks, with no active spots.

Acne Scarring

The reviewed sources do not establish this ingredient as a treatment for this concern.

How it works

Niacinamide mechanism diagram. Supports the skin barrier: Helps skin make lipids that reduce water loss. Reduces pigment transfer: Less pigment reaches neighboring skin cells. — Open full-size diagram
Diagram explanation and sources
Supports the skin barrier: Helps skin make lipids that reduce water loss. Reduces pigment transfer: Less pigment reaches neighboring skin cells.
Schematic illustration; not a measurement of skin penetration. Effects vary with ingredient identity and formulation.
Source 1 · Source 2 · Source 3 · Source 4

Sulfur mechanism diagram. Helps loosen surface keratin: Sulfur preparations can promote exfoliation. Acts against microbes: Effects depend on the preparation and intended use. — Open full-size diagram
Diagram explanation and sources
Helps loosen surface keratin: Sulfur preparations can promote exfoliation. Acts against microbes: Effects depend on the preparation and intended use.
Schematic illustration; not a measurement of skin penetration. Effects vary with ingredient identity and formulation.
Source 1 · Source 2 · Source 3

Using both in one routine

Built from where each one usually sits in a routine. Introduce one at a time.

Morning

Step 1

Cleanser

Step 2

NiacinamideMorning or night

Step 3

Moisturizer

Step 4

Sunscreen

Night

Step 1

Cleanser

Step 2

NiacinamideMorning or night

Step 3

SulfurNight

Step 4

Moisturizer

Strengths and forms

Concentrations

Clinical studies commonly use 2–5% niacinamide for particular concerns. Higher marketed strengths are not a proven upgrade for everyone.

2%

4–5%

10%

Studied for facial oiliness

Controlled studies tested a finished formula for measures of facial oiliness; results do not mean every oily skin needs niacinamide.

Studied for tone and skin aging

Different trials studied pigmentation, melasma or fine lines. The concern and finished formula matter.

Higher marketed concentration

Available in skincare, but not established as universally more effective than the lower studied strengths.

Choosing a strength: A comfortable 2–5% product is a reasonable place to look when choosing for the studied concerns; evaluate the complete formula.

Higher strengths: Higher percentages may sting or irritate some skin. Do not keep increasing the concentration when the product causes discomfort.

Formula matters: Niacinamide is also included in moisturizers without a stated percentage. That does not mean the moisturizer cannot support skin comfort.

Sulfur strength depends on the condition: U.S. OTC acne products use 3–10%, while compounded scabies ointments use a separate 5–10% range.

3–10%

5–10%

OTC acne range

For qualifying acne products. A wash, mask and leave-on product have different contact instructions.

Compounded scabies ointment

A clinician-directed alternative discussed by CDC. It is a separate treatment, not ordinary facial skincare.

Choosing a strength: Choose for the diagnosis and complete product. Sulfur-only acne products and prescription sulfacetamide/sulfur combinations are not the same.

Higher strengths: More sulfur is not automatically more useful, and dryness or irritation may limit use.

Formula matters: Wash-off versus leave-on use matters. Scabies treatment requires a whole treatment plan rather than choosing a percentage alone.

Forms

Serum · Moisturizer · Toner

Mask · Spot treatment · Wash

When you’ll see results

Approximate windows, not promises.

● Niacinamide

● Sulfur

First few weeks

First few weeksAssess comfort. Moisturizer benefits may appear before changes in tone or lines.

First few weeksAssess tolerance and texture; immediate softness can come from the base formula.

4–8 weeks

4–8 weeksOiliness or uneven pigmentation may begin to improve.

4–8 weeksSubtle changes may appear in some tested products; evidence varies.

8–12 weeks

8–12 weeksReassess tone and fine lines; expect modest changes.

8–12 weeksCompare photographs in the same lighting and reassess benefit.

3–6 months

3–6 monthsContinue if it helps and remains comfortable.

3–6 monthsPhotoaging trials often need several months; expect modest rather than dramatic change.

6–12 months

6–12 monthsLong-term benefit is less well defined than short-term results.

6–12 monthsLong-term evidence is limited for many cosmetic actives; continue only if useful.

Safety and sensitive skin

Common reactions

Stinging, redness, dryness or a rash can occur. Fragrance, preservatives and other ingredients may also contribute to a reaction.

Odour, dryness and irritation can limit use; avoid strong products on inflamed eczema.

When to stop

Stop for persistent burning, swelling or an itchy rash. Seek urgent help for trouble breathing or rapidly worsening facial swelling.

Stop for persistent burning, swelling, blistering or a new rash. Seek urgent care for breathing difficulty or a severe allergic reaction.

Sensitive or inflamed skin

Choose a gentle formula and test a small area. Barrier-support claims do not mean every product suits rosacea or eczema.

Choose a simple formula and test a small area first. Individual tolerance matters more than an ingredient’s reputation for being gentle.

Pregnancy & breastfeeding

This topical ingredient is not a retinoid. Review the complete product with your clinician; do not assume every combination formula is suitable.

Not covered in this guide yet

Important limits

Niacinamide supports skincare; it does not replace diagnosis or established treatment of persistent acne, melasma or an inflamed rash.

Do not use a cosmetic product as a substitute for diagnosis of an unexplained, changing or persistent skin problem.

Pregnancy

Not covered in this guide yet

Topical sulfur is generally considered acceptable in pregnancy; ask the clinician managing your pregnancy.

How it works

In the skin

On the skin. A water-soluble vitamin used in serums and moisturizers.

Entering skin. Human studies show delivery into the outer skin; uptake depends on the formula.

Conversion. Cells use niacinamide to help make NAD+, which supports energy and repair.

Skin response. Supports production of barrier lipids, including ceramides, and helps reduce water loss.

Additional effects. Reduces pigment transfer between skin cells in laboratory models.

On the skin. The finished product delivers sulfur in a particular vehicle.

Entering skin. Below 500 Da in this molecular form. Its useful surface action does not require deep delivery; the formula and skin condition matter.

Conversion. No activation step is established as necessary for its intended topical role.

Skin response. Promotes surface shedding and has antimicrobial activity; effects and instructions depend on the preparation.

Additional effects. Proposed pathways do not establish a measured depth of delivery or clinical benefit beyond the studies cited.

Getting in

Below the 500 Da guideline. Human studies show that the formula strongly affects uptake.

Below 500 Da in this molecular form. Its useful surface action does not require deep delivery; the formula and skin condition matter.

Molecule size

Niacinamide · 122 Da

Sulfur · 256 Da

Smaller than 500 Da passes the outer skin more easily. Size isn’t an effectiveness score.

500 Da guideline

Product examples

Niacinamide

The Ordinary Niacinamide 10% + Zinc 1% — Budget serum.
Paula’s Choice 10% Niacinamide Booster — Mixes into moisturizer.
CeraVe PM Facial Moisturizing Lotion — Niacinamide plus ceramides.

Sulfur

Murad Rapid Relief Acne Sulfur Mask
The Ordinary Sulfur 10% Powder-To-Cream Concentrate
Naturium The Revealer Sulfur Body Wash

Common questions

Niacinamide:Does niacinamide help fine lines?

There is clinical evidence, including a small 12-week controlled trial of a 5% moisturizer. Expect modest improvement; it does not erase deep wrinkles.

Niacinamide:Is 10% better than 5%?

Not necessarily. Many clinical studies used 2–5%, and a higher concentration is not proven to work better for every concern.

Niacinamide:Can niacinamide treat acne by itself?

Small trials suggest benefit, but the evidence is limited. Persistent, painful or scarring acne needs an established acne treatment plan.

Niacinamide:Does niacinamide permanently shrink pores?

That has not been established. Less oil or a smoother appearance can make pores look less obvious without permanently changing their structure.

Niacinamide:Why does my niacinamide product sting?

The concentration, other ingredients or your skin barrier may be responsible. Reduce use or stop if irritation persists; you do not need to push through it.

Sulfur:What should I choose sulfur for?

Consider for an appropriate acne product; suspected scabies needs diagnosis and a complete plan.

Sulfur:How strong is the evidence?

Modern isolated-sulfur acne evidence is limited; studies of sulfacetamide/sulfur cannot isolate sulfur. CDC describes sulfur ointment as a scabies option, but an acne wash is not a substitute for that regimen.

Sources

Sources and further reading

Dermapedia on YouTube