Ingredient glossary

Sulfur

What Sulfur does for your skin, who it suits, and what to watch for.

INCI: Sulfur · Also: Precipitated Sulfur

Solid and proven

In short: Sulfur delivers anti acne and keratolytic, suits oily skin best, and the evidence behind it is moderate. One thing to know: clear it with your doctor if pregnant; introduce it gently.

What it does
Anti acne, keratolytic
Best for
Oily skin
Watch out
Clear it with your doctor if pregnant; introduce it gently
Evidence
Moderate
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The Glow take

Genuinely worth a spot in your routine.

When your goal is calming breakouts and congestion, Sulfur pulls genuine weight, with a solid amount of evidence behind it. Introduce it gently, and pair it with something soothing if your skin runs sensitive.

— Maya

What it does

  • anti acne
  • keratolytic
  • antimicrobial

moderate evidenceHistorical and modern data support three to ten percent sulfur in acne and seborrheic dermatitis with clear lesion reductions though high quality contemporary RCTs are fewer than for newer agents.

On a label: usually effective at 3-10%.

Who it's for, and who should skip it

Tends to suit

  • oily
  • acne prone
  • seborrheic dermatitis

Approach with care

  • very sensitive
  • dry
  • compromised barrier
  • Clogs poresModerate
  • Irritation riskModerate

How it fits each skin type

  • DryTake care
  • CombinationNeutral
  • OilySuits
  • SensitiveTake care

Often chosen for acne prone, seborrheic dermatitis. Take extra care if any of these apply to you: compromised barrier.

Where it fits in your routine

WhenMorning or evening
Where in the orderAfter cleansing, before your moisturizer

Plays well with

Sulfur, answered

Is Sulfur safe during pregnancy?

Clear it with your doctor first. Sulfur is flagged as use-with-caution during pregnancy and breastfeeding, so check with your doctor or midwife before adding it.

Who should avoid Sulfur?

Approach Sulfur with care if any of these apply to you: very sensitive, dry, and compromised barrier. Its irritation risk is moderate, so introduce it slowly and patch test first. It carries a moderate risk of clogging pores, so acne-prone skin should go carefully.

What concentration of Sulfur actually works?

Sulfur tends to do its job in the 3 to 10% range. Much lower and it is likely underdosed.

During pregnancy

Treat Sulfur as a maybe rather than a yes for now. It is flagged as one to use with caution while pregnant or breastfeeding, so it is worth clearing before you carry on.

When in doubt, check with your doctor or midwife. They outrank any website, including this one.

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Sources & how we reviewed this

Last reviewed July 2026. Educational information about a cosmetic ingredient, not medical advice.