Hyperpigmentation is one of the most common skin concerns and affects people of all ages and skin tones. It is also one of the most difficult to treat. One of the main reasons is that not all hyperpigmentation is the same. It varies in its cause, depth and location, so the right treatment depends on identifying which type you have. In this article we explore what causes hyperpigmentation and the best treatments for it.
What Causes Hyperpigmentation?
All hyperpigmentation shares the same underlying process. The skin overproduces melanin, the pigment that gives skin its colour. Melanocytes make this melanin and pass it up into the surrounding skin cells. Melanin is also the skin’s natural defence against UV and injury. This is why anything that signals damage or irritation (from sunlight to an acne spot or burn) can ramp up production through an enzyme called tyrosinase. The main triggers of hyperpigmentation include:
- Sun exposure: This is the single biggest driver of hyperpigmentation. UV makes melanocytes produce more melanin as a protective response, and it worsens almost every other type of pigmentation. It is also the main reason pigmentation recurs after treatment.
- Inflammation & injury: Any insult to the skin (acne, eczema, a burn, a cut, friction or a procedure) can trigger post-inflammatory hyperpigmentation. Inflammatory mediators such as prostaglandins and reactive oxygen species stimulate melanocytes, which deposit excess pigment as the skin heals. It is especially common after acne. In one study of acne in skin of colour, it affected 65.3% of African-American, 52.7% of Hispanic and 47.4% of Asian patients.
- Hormones: Oestrogen and progesterone can stimulate melanocytes. This is why melasma often flares in pregnancy (also called chloasma), on the combined contraceptive pill or with HRT. Heat and UV make it worse.
- Ageing & accumulated sun exposure: Years of cumulative UV exposure leave clusters of overactive melanocytes, which show up as sun spots on the face, hands, chest and arms. These are also called age spots, liver spots or solar lentigines.
- Genetics & skin tone: A family history is common, and people with skin of colour are naturally more prone. Their melanocytes are larger, produce more melanin and are more reactive.
- Medication: Some drugs cause drug-induced pigmentation, including certain antimalarials, tetracyclines, chemotherapy agents and tricyclic antidepressants.
- Medical conditions: Less commonly, generalised darkening can signal an underlying condition such as Addison’s disease or haemochromatosis. Urgently see a doctor about any patch that changes in size, shape or colour, as an early melanoma can look like a simple dark spot.
What are the Different Types of Hyperpigmentation?
Hyperpigmentation falls into a few main categories which are grouped by cause and appearance. This matters because it can affect treatment choice. The main types of hyperpigmentation are:
- Sun & age spots: Flat brown spots (solar lentigines) on sun-exposed areas. They respond well to topical treatment and good sun protection.
- Melasma: Larger, symmetrical patches on the forehead, cheeks, upper lip and nose, driven by hormones, UV and heat. Melasma is the most stubborn type and tends to relapse, so it needs ongoing management rather than a one-off fix.
- Post-inflammatory hyperpigmentation: Flat brown or grey marks left behind by acne, injury or a procedure. PIH usually fades over months, though the deeper the pigment sits, the longer it takes.
- Freckles: Small genetic spots (ephelides) that darken with sun and fade in winter. They are harmless and need no treatment, though sun protection keeps them lighter.
Why Does the Depth of Hyperpigmentation Matter?
How deep the pigment sits is one of the most important factors, because depth largely predicts how treatable it is. There are two broad levels of hyperpigmentation:
- Epidermal: This is superficial pigment that sits in the surface layers, usually light to dark brown. Epidermal hyperpigmentation responds relatively well to topical treatment and fades faster.
- Dermal: Here pigment has dropped through a damaged dermo-epidermal junction into the deeper skin, known as pigment incontinence. It often looks grey or blue-grey, is far more stubborn, and topical creams reach it poorly.
Most cases of hyperpigmentation are mixed, with pigment at both levels. This can mean that the hyperpigmentation only partially responds to more simple treatments. A doctor can often judge the depth from the colour and with the aid of a Wood’s lamp. Determining the depth is helpful for setting realistic expectations and choosing the right treatment.
Does Hyperpigmentation Affect Skin of Colour Differently?
Hyperpigmentation behaves differently in skin of colour, and that affects how it should be treated. People with skin of colour have more active melanocytes, so the skin makes and holds pigment more readily. This makes hyperpigmentation, and PIH in particular, more common, more intense and longer-lasting in deeper skin tones. It also means strong actives and aggressive procedures carry a higher risk of triggering even more pigment deposition. For this reason, a gentler approach is usually necessary.
How is Hyperpigmentation Treated?
Because hyperpigmentation has so many causes, there is no single fix. The right treatment depends on the cause, the depth and your skin tone. Most plans combine a few of the following:
- Sun protection: A daily broad-spectrum SPF 30 or higher underpins every plan. Without it, melanin production keeps firing and the pigment returns.
- Pigment suppressors: These slow melanin production by blocking the enzyme tyrosinase. Hydroquinone is the most effective and the gold standard for stubborn pigment. It is prescription-only and used in short courses. Gentler alternatives include azelaic acid, kojic acid, arbutin and vitamin C. These are also useful for maintenance.
- Tranexamic acid: This works on a different pathway and is especially useful for melasma. It suppresses pigment and also calms the underlying redness. It comes as a topical or, in resistant cases, oral tablets.
- Retinoids: These fade pigment by speeding up cell turnover and help other actives penetrate. Tretinoin and adapalene are the most active and are prescription-only. Gentler retinoids are available over the counter.
- Exfoliating acids: AHAs such as glycolic, lactic and mandelic acid lift away pigmented surface cells. Salicylic acid (a BHA) suits oily, acne-prone skin. Milder acids like mandelic and lactic are safer in skin of colour.
- In-clinic treatments: Chemical peels and laser or IPL can target deeper or resistant pigment that creams cannot reach. They need a course of sessions and carry a higher risk of PIH in darker skin. A practitioner experienced in treating deeper skin tones is therefore essential.
How to Prevent Hyperpigmentation
Whilst there’s not much you can do about genetic causes, it is possible to prevent or limit most acquired hyperpigmentation. The best ways to prevent hyperpigmentation include:
- Protect against the sun: A daily broad-spectrum SPF 30 or higher, plus shade and a hat, is the single most effective step.
- Treat inflammation early: Getting acne and eczema under control and not picking or squeezing spots can prevent most PIH.
- Introduce actives carefully: Strong acids and retinoids can irritate and trigger pigment, especially in skin of colour, so introduce them slowly.
- Choose your practitioner carefully: Only have peels or laser with an experienced medical practitioner. Very often, a poorly performed procedure is itself a common cause of PIH.
At City Skin Clinic, our doctors create personalised prescription treatments to fade hyperpigmentation, even out skin tone and brighten the complexion. Where suitable, we combine actives like hydroquinone, tretinoin, azelaic acid and tranexamic acid into custom treatments designed around your skin and goals. To start your personalised skincare plan, book a virtual video consultation or use our online consultation form. The journey towards great skin starts here.
This article is intended for general informational purposes only and is not a substitute for medical advice, diagnosis or treatment. Always consult a qualified medical professional with any concerns about your skin or treatment options.
