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Sulfur

SulfurExfoliant

Old-school acne ingredient with modest but consistent evidence — limited mostly by smell and dryness.

What it does

Sulfur is one of the longest-used topical acne ingredients with antimicrobial and mild keratolytic action against inflammatory acne and seborrheic dermatitis. Most modern formulations use 3–10% in masks or short-contact treatments rather than leave-on, because tolerability is the main limitation: characteristic odor, dryness, and occasional flaking drive most users to spot or short-contact use. Effects build over weeks of consistent use.

The evidence, graded

expert consensusTopical sulfur kills fungi and bacteria and loosens dead skin. It has shown benefit in acne, rosacea and seborrhoeic dermatitis, alone or paired with sodium sulfacetamide or salicylic acid. Side effects are rare and mostly mild reactions where it is applied.Gupta 2004 · Journal of drugs in dermatology ↗

Graded per the methodology: strong · moderate · emerging · expert consensus. A weak source on a strong claim gets the weaker label.

Also known as

colloidal sulfur, precipitated sulfur

Pairs worth knowing

Niacinamide (Vitamin B3) · works together ↗Azelaic Acid · works together ↗Salicylic Acid · works together ↗

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