What Works Skin — Independent · Evidence-First · Ad-FreeIssue 014 · 20 April 2026 · Next: 04 Maywhatworksskin.com
What WorksSkin
Search/

Concern · Pigmentation · Solar lentigines

P. 23 · GUIDE

The flat brown spots
that read as age.

Cumulative UV damage. Prevention beats correction.

Solar lentigines — the flat, sharply-edged brown patches on cheeks, dorsal hands, and forearms. Distinct from melasma in pattern, distinct from PIH in trigger, distinct from seborrheic keratoses in texture. Prevention is cheap; correction is harder.

— § 01

The triggers worth tracking.

Sharply demarcated brown / tan macules

The defining feature. Edges are crisp; colour is uniform; surface is flat. If raised, consider seborrheic keratosis.

96%
Sun-exposed sites: cheeks, hands, forearms

Distribution maps to lifetime UV dose. The dorsal hands often outpace the face in the 50s.

89%
Increases gradually after age 40

Cumulative dose-response. Onset before 40 is unusual and warrants a closer look.

78%
No itch, no irritation, no growth

Static. New, growing, or itching pigmented lesions need a clinic visit, not a serum.

85%
⁂

— § 02

Ingredients that actually work.

Tier
Molecule
Role
Evidence
Tier A
Mineral SPF 50+ daily
Prevention
The single highest-leverage variable. The Australian RCT remains the reference.
Tier A
Hydroquinone 4%
Tyrosinase inhibitor
First-line for established lentigines. Cycle 3 months on, 2 off.
Tier A
Tretinoin 0.025–0.05%
Cell turnover
Doubles the response when paired with hydroquinone. The classic Kligman cocktail.
Tier B
Glycolic 8–10% leave-on
Surface exfoliation
Adjunct, not solo. Useful for textural unevenness over time.
Tier A
Q-switched laser (clinic)
Selective destruction
Single-session clearance for discrete lentigines. The procedural gold standard.
Tier B
Cryotherapy (clinic)
Selective destruction
Effective; risk of post-procedure hypopigmentation in darker skin.
⁂

— § 03

The protocol.

  1. Phase 01 · Week 1–8

    SPF + topical start

    Mineral SPF 50+ daily. Begin Kligman cocktail (hydroquinone + tretinoin + low-potency steroid) at night, 5 nights a week.

  2. Phase 02 · Week 8–12

    First photo check

    8-week response is your decision point. If significant fade, continue another 4 weeks. If minimal, escalate to clinic.

  3. Phase 03 · Month 4

    Procedural option

    Q-switched laser is the most efficient single-session route for stubborn lentigines. Pair with continued SPF.

  4. Phase 04 · Maintenance

    Lifelong SPF

    Pigment returns within 2 years of inconsistent SPF. Treat sunscreen as the prevention drug it is.

Bottom line

The category where prevention is dramatically cheaper than correction. People who started SPF in their 30s do not have this conversation in their 50s.