Dark Spots and Melasma: Causes, When to See a Doctor and What Treatments Are Available

Why do dark spots form on the skin?

Skin colour is determined by melanin pigment, which is produced by cells called melanocytes. These cells can produce more pigment in response to triggers such as sunlight, hormones or inflammation in the skin. When pigment builds up in one area, it leads to areas that look darker than their surroundings, that is, hyperpigmentation.

It is important to understand the type of spot, because a treatment that works for one type of spot may be ineffective for another or may make it worse. For this reason, the spot needs to be assessed by a doctor before treatment is started.

Common types of dark spots

Freckles, birthmarks and moles are also pigmented features of the skin; however, they are different structures and are assessed separately.

What is melasma, and who gets it?

Melasma is a long-lasting pigment disorder with a strong tendency to come back, appearing as brown-grey patches on the face, usually in similar positions on both sides. It is much more common in women; however, it can also occur in men. It is more common in people with medium to dark skin and in those with a family history of melasma.

Melasma that appears during pregnancy is also popularly called the “mask of pregnancy”. Some of it may fade over time after giving birth, but it may reappear in later pregnancies.

Factors that trigger and worsen dark spots

• Sunlight: the most common trigger and aggravating factor for spots. Even short exposure can darken melasma.
• Visible light and heat: especially in melasma, it is thought that not only ultraviolet (UV) light but also visible light and heat can worsen the spots.
• Hormonal influences: pregnancy, hormone-containing medicines such as the contraceptive pill, and hormone therapies
• Some medicines: certain medicines that cause sensitivity to light or can lead to increased pigmentation
• Irritating cosmetic products and perfumed products: can contribute to spot formation by causing inflammation in the skin.
• Skin inflammation: acne, eczema, friction, burns or unsuitable procedures

If you think a medicine you are taking may be related to your spots, do not stop the medicine on your own; first consult the doctor who prescribed it.

When should you see a doctor?

Most spots are harmless; however, some dark spots can be a sign of melanoma, a type of skin cancer. When melanoma is caught early, the chances of successful treatment are high. For this reason, if you notice any of the following changes, see a dermatologist without delay:

Also, if your spots are increasing rapidly, are appearing not only on the face but also on parts of the body not exposed to the sun, or if there are other symptoms such as fatigue, a doctor’s assessment is needed to rule out another underlying disease.

The foundation of treatment: sun protection every day

Whatever treatment is chosen, lasting improvement cannot be expected without sun protection. When you stop protecting yourself from the sun, spots can darken again within a short time.

• Use a broad-spectrum (protecting against UVA and UVB), high-protection-factor sunscreen every morning, including on cloudy days and in winter.
• If you are outdoors, reapply sunscreen about every two hours, and more often after sweating or swimming.
• For melasma, your doctor may recommend tinted sunscreens (containing iron oxide) that also protect against visible light.
• A wide-brimmed hat, sunglasses and shade complement sunscreen.
• Avoid direct sun around midday, when the sun is strongest.
• Stay away from sunbeds.

Creams and medicines a doctor may recommend

There are many active ingredients used for dark spots. Some reduce pigment production, others speed up skin renewal. Your doctor decides which one to use, how often and for how long, depending on the type of spot and your skin.

• Substances that reduce pigment production (for example hydroquinone; used under a doctor’s supervision and for periods set by the doctor)
• Vitamin A derivatives (retinoids)
• Milder substances such as azelaic acid, kojic acid and niacinamide
• Where the doctor considers it appropriate, combination creams containing certain substances together

“Whitening” products of unknown content bought online or without a prescription for dark spots may cause permanent skin damage or paradoxical darkening, or may contain substances harmful to health. Do not use prescription creams for longer than recommended either.

Creams work slowly. It often takes several months to see a noticeable change; regular use and sun protection are necessary during this time.

What procedures are available?

When creams and sun protection alone are not enough, your doctor may recommend certain procedures. These procedures are usually used together with creams rather than instead of treatment.

• Chemical peel: allows the upper layers of the skin to renew in a controlled way. You can find details in our article “Chemical Peels: What They Are, Who They Suit and What Recovery Involves”.
• Laser and IPL (intense pulsed light): can be effective especially for sun spots with well-defined edges. The general working principles of light treatments and their relationship to skin type are also explained in our article “Laser Hair Removal”.
• Other methods such as microneedling: may be tried in some patients together with other treatments; the evidence is limited.

Caution with melasma: some laser and light treatments, especially at high energy, can create heat and inflammation in the skin and make melasma and post-inflammatory spots worse. For melasma, laser and IPL should only be considered in carefully selected patients, with suitable settings and by an experienced doctor.

In people with dark skin, the risk of post-inflammatory spots after both peels and laser is higher. For this reason, the choice, intensity and frequency of procedures should be planned individually.

Realistic expectations

• Sun spots can usually fade noticeably; however, new ones will appear if you do not protect yourself from the sun.
• Post-inflammatory spots may fade on their own over time once the cause has gone; this period varies from person to person and may be longer on dark skin; treatment can help speed up this process.
• Melasma is a long-lasting condition with a tendency to come back. Treatment can achieve noticeable fading, but the spots may return when treatment is stopped or when there is sun exposure.
• With melasma, the aim is often not to remove the spots completely but to keep them under control. For this reason, maintenance care and sun protection are continued for a long time after treatment.
• A definite result is not achieved with a single procedure; patience and regular follow-up are needed.