Azelaic Acid

What it does

A gentle multitasker: fades dark spots, calms redness (including rosacea-prone skin) and clears mild acne. The 10% strength is the common over-the-counter one, and it's one of the best-tolerated actives going.

How to use it

Thin layer as a serum, morning or night. No real scheduling enemies - it's the active people use when everything else stings.

What not to mix it with

No scheduling enemies in Nitavera's 15 conflict pairs - this one layers easily.

What it gets along with

Plays nicely with essentially everything, including niacinamide, hydrators and (for most people) retinoids.