Open Skin Lab
Concern guide

Dark spots

Dark spots form when pigment cells make too much melanin in one patch, often after sun or a breakout. Fading them takes daily sunscreen, the right active and a few months.

See it inside skin in 3DStarter routine
Surface filmBarrierLiving epidermisDermis

What’s happening

Melanocytes at the base of your epidermis make melanin and pass it up to surface cells. UV light and inflammation, like a healed breakout, can push one area into overdrive, leaving a darker patch.

Common triggers
Sun exposureMarks left after breakoutsPicking or irritationHormonal changes (melasma)Skipping sunscreen

What helps

Ranked for this concern. Tap one for its full guide.

Sunscreen

Stops UV from making new pigment. Without it, other treatments can’t keep up.

Best match
Azelaic acid

Slows melanin production. Performed about as well as 4% hydroquinone for melasma in a large trial.

Best match
Niacinamide

Slows the hand-off of pigment packets to surface cells.

Good match
Vitamin C

Slows tyrosinase and counters UV damage. Best in the morning.

Good match
Retinol

Speeds turnover so pigmented cells shed sooner. Slow, and needs a gentle start.

Good match
Glycolic acid

Exfoliates pigmented surface cells. Raises sun sensitivity.

Good match

A simple starter routine

Start here, then add one new product at a time.

☀ Morning
1
Gentle cleanserMorning
2
Vitamin COr niacinamide if vitamin C stings
3
MoisturizerKeep skin comfortable
4
SunscreenSPF 30+, reapply every 2 hours outdoors
☾ Night
1
Gentle cleanserNight
2
Azelaic acidOr niacinamide; add retinol or glycolic acid later, on separate nights
3
CeramidesMoisturizer with ceramides

Mistakes to avoid

  • Skipping sunscreen, even on cloudy days
  • Picking at spots or breakouts
  • Using strong acids so often that skin gets irritated, which can cause new marks
  • Expecting results in a week: studies run for months
When to see a doctorSee a dermatologist about any spot that is new, changing in size, shape or color, bleeding or itching. Melasma that doesn’t respond to sunscreen and gentle treatment also deserves a doctor’s visit.

Sources

  1. Hakozaki T, et al. Niacinamide and melanosome transfer. Br J Dermatol. 2002. PubMed
  2. Feng X, et al. Azelaic acid: mechanisms of action and clinical applications. Clin Cosmet Investig Dermatol. 2024. Article
  3. Al-Niaimi F, Chiang NYZ. Topical vitamin C and the skin. J Clin Aesthet Dermatol. 2017. PMC
  4. UCSF Health. Sunscreen for skin cancer prevention. UCSF
Draft: pending review by a dermatologist or cosmetic chemistLast updated 6 Nov 2026