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Melasma and acquired hyperpigmentation
Melasma is chronic, symmetric facial hyperpigmentation driven by light (UV and visible light), hormones and genetic tendency; the basic treatment is strict light protection, including visible light, plus lightening agents — mainly triple combination with hydroquinone.
Why it matters in the exam
The exam shows a woman of reproductive age with symmetric brown patches on the cheeks, forehead and upper lip that appeared in pregnancy or on the pill and worsened in summer. The question tests the diagnosis, the distinction from post-inflammatory hyperpigmentation, nevus of Ota, solar lentigo and lentigo maligna melanoma, and the treatment: a mineral sunscreen with iron oxide (which also blocks visible light), triple combination of hydroquinone, tretinoin and a mild steroid, and oral tranexamic acid in resistant cases. Side effects are also asked: exogenous ochronosis from long-term hydroquinone, and worsening after aggressive laser in darker skin. Remember that the disease tends to recur, that treatment is long, and that it is important to set expectations with the patient. In men melasma is less common but exists, and occupational sun exposure and drugs should be asked about. Heat, infrared radiation and irritating cosmetics can also worsen the patches.
Key points
- Melasma is chronic symmetric facial hyperpigmentation driven by light, hormones and genetic tendency.
- The basis of treatment is strict light protection, including visible light, with an iron-oxide sunscreen.
- Triple combination of hydroquinone, tretinoin and a mild steroid is the most effective topical treatment, for a limited period.
- Oral tranexamic acid is effective in resistant cases but is contraindicated in patients with a thrombosis risk.
- Melasma must be distinguished from post-inflammatory hyperpigmentation, solar lentigo, nevus of Ota and lentigo maligna.
Summary table
| Condition | Appearance | Causes | Treatment |
|---|---|---|---|
| Melasma | Symmetric brown patches on the cheeks, forehead and upper lip | UV and visible light, pregnancy, contraceptive pill, genetic tendency | Light protection with iron oxide, triple combination, azelaic acid, tranexamic acid |
| Post-inflammatory hyperpigmentation (PIH) | Dark patches at sites of earlier acne, eczema or injury | Common in darker skin | Treat the underlying inflammation, light protection, lightening agents |
| Solar lentigo | Sharp brown macules on the backs of the hands and the face in older age | Cumulative sun damage | Cryotherapy, laser; distinguish from lentigo maligna |
| Nevus of Ota | Unilateral blue-grey patch around the eye, including the sclera | Dermal melanocytes, congenital or at puberty | Q-switched laser; glaucoma follow-up |
| Acanthosis and drugs | Darkening in folds; blue-grey drug pigmentation | Minocycline, amiodarone, antimalarials | Stop the drug; some remains |
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Sources
- Global consensus on melasma management (Pigmentary Disorders Academy), 2023 — Treatment ladder
- British Association of Dermatologists patient and clinical guidance on melasma, 2021 — Topical treatment
- Fitzpatrick's Dermatology, 9th edition (2019) — Disorders of hyperpigmentation
Sources are given for further reading; the text is written afresh and not copied from them.
Reviewed by the Examqo AI Professor · 2026-11-06. The text may contain errors; when in doubt, check the source.