How to treat hyperpigmentation — what the evidence shows.

Hyperpigmentation — patches or areas of skin that appear darker than the surrounding tissue — is one of the most common skin concerns across all skin types and tones. It is also one of the most misunderstood, in part because the category includes several distinct conditions that respond to different interventions.

Understanding the mechanism behind hyperpigmentation is more useful than any single product recommendation.

What causes hyperpigmentation

The darkening in hyperpigmentation is caused by an excess of melanin — the pigment produced by melanocyte cells in the skin's basal layer. Melanin itself is not a problem; it is the skin's primary defence against UV radiation. Hyperpigmentation occurs when melanin production becomes dysregulated or localised.

There are three main types:

Post-inflammatory hyperpigmentation (PIH) results from inflammation — acne, a wound, an aggressive chemical peel, or any other skin trauma. The inflammatory response triggers excess melanin production at the site. PIH is more pronounced and longer-lasting in darker skin tones because melanocytes in darker skin are more reactive to inflammation.

Melasma is a chronic condition characterised by symmetrical patches, typically on the face, caused by a combination of hormonal factors (oestrogen, progesterone) and UV exposure. Melasma is significantly harder to treat than PIH because the triggering factors are ongoing; it tends to recur even after successful treatment if sun protection is inadequate.

Sun damage (lentigines / solar freckles) results from cumulative UV exposure accelerating localised melanin production. Unlike PIH, these are not triggered by inflammation — they are a direct response to UV radiation over time.

What actually works

The ingredients with the strongest evidence for treating hyperpigmentation address the melanin production pathway at different points.

Niacinamide inhibits the transfer of melanin-containing vesicles (melanosomes) from melanocytes to the keratinocytes that form the visible skin surface. At concentrations of 4–10%, it has consistent evidence for reducing the appearance of hyperpigmentation over 8–12 weeks. It is well tolerated across skin types, including darker tones where irritation from other actives can worsen PIH.

Vitamin C (L-ascorbic acid) inhibits tyrosinase — the enzyme that catalyses the first step of melanin synthesis. It also functions as an antioxidant, neutralising the reactive oxygen species that trigger melanin production in response to UV exposure. At 10–20% concentration in a stable formulation, vitamin C has good evidence for brightening over time. It is photosensitising and best applied in the morning under SPF.

Retinoids accelerate cell turnover, which helps move pigmented cells toward the surface and off the skin faster. They also have a mild inhibitory effect on tyrosinase. Retinoids are more useful for maintaining treatment results and preventing new pigmentation than for rapidly clearing existing hyperpigmentation.

Azelaic acid (10–20%) inhibits abnormally active melanocytes while leaving normal melanocytes unaffected — making it particularly useful for PIH and melasma. It is also anti-inflammatory, which addresses one of the underlying triggers of PIH directly. It is safe in pregnancy and well tolerated by sensitive skin.

Alpha arbutin and kojic acid inhibit tyrosinase with evidence for efficacy at established concentrations, though the evidence base is somewhat thinner than for the ingredients above.

What does not help

Sun exposure. This is the most significant confounding factor in hyperpigmentation treatment. UV radiation stimulates melanin production directly and triggers the inflammatory pathways that cause PIH. Treating hyperpigmentation without daily broad-spectrum SPF is close to futile — the treatment makes progress and the sun reverses it.

Aggressive exfoliation. Physical scrubs and high-strength acids do not bleach pigmentation. They remove the top layer of skin, which can temporarily reduce the appearance of surface pigmentation — but they also cause inflammation, which in PIH-prone skin makes the underlying condition worse.

Timeline expectations

Hyperpigmentation takes time to resolve. The skin's natural turnover cycle is approximately 28–40 days; for deeper pigmentation or melasma, the treatment timeline is measured in months, not weeks.

A realistic treatment trajectory: 8–12 weeks of consistent use of the right active (niacinamide, vitamin C, or azelaic acid) under daily SPF produces measurable improvement. Melasma often requires longer and ongoing maintenance. PIH, particularly from resolved acne, can clear significantly within 3–6 months with the right routine and no new triggering inflammation.

The Lux & Glo position

The niacinamide serum addresses hyperpigmentation through the melanosome transfer pathway — consistently, gently, and without the irritation risk that can worsen PIH. At an effective concentration, and used daily, it is among the most broadly suitable active ingredients for this concern across all skin tones.

The most important co-intervention is the one no serum replaces: daily SPF. Whatever active you choose for hyperpigmentation, sunscreen is not optional — it is the mechanism by which the active's effect is preserved.