Melasma

Melanin, as we know, is a pigment in our skin. It performs important functions like blocking the harmful rays of the sun. Melasma occurs when the cells that make melanin—melanocytes—malfunction.

The most obvious symptom of melasma is hyperpigmentation or spots on the face, though these spots may also occur on the neck, shoulders and forearms.

The spots of melasma can be brown or greyish-brown: if the hyperpigmentation is in the deeper layers of the skin (dermis), the spots appear greyish-brown and less defined (the boundary is less clear) compared with when the spots are in the epidermis or upper layer of skin.

Melasma spots are usually diffused and spread symmetrically: across the bridge of the nose, on both cheeks, etc. This is a key clue in separating melasma from some other skin pigmentation disorders like dark circles around the eyes.

Facial spots of melasma are typically found in three patterns:

• Centrofacial, with spots on the forehead, nose, cheekbones and chin
• Spots on both cheeks
• Mandibular, with spots centred around the jaw

The spots in other parts of the body tend to be located in regions that have higher exposure to the sun, such as the neckline and forearms.

Melasma is a type of skin pigmentation problem. Though doctors don’t exactly know what causes melasma, there has been some research on the mechanism (what happens in the body) and risk factors of melasma.

The risk factors of melasma include:

• Being a woman
• Having darker skin tone, but not skin type VI where melanin is already produced at "maximum efficiency"
• Pregnancy
• Being on a birth control pill (combined contraceptive pill)
• Excess exposure to the sun’s UV rays
• Family history of melasma
• Thyroid disorders

Of these, melasma during pregnancy and melasma due to contraceptive pills tend to go away after delivery or when you stop taking the pills, respectively.

Melasma spots are usually easy to recognise by appearance: brown or greyish brown spots that are symmetrical (equal on both sides) and have ill-defined boundaries. That said, melasma is only one of many different skin hyperpigmentation disorders such as:

• Maturational dyschromia, in which the cheeks and forehead appear darker than the rest of the face
• Periorbital hyperpigmentation or dark circles under the eyes
• Riehl melanosis, a kind of pigmented contact dermatitis in which brown‐grey spots appear on the face, usually as a reaction to some cosmetics
• Exogenous ochronosis occurs because of long-term use of hydroquinone—one of the drugs that may be prescribed for melasma treatment. It appears as banana-shaped yellowish spots under the skin
• Acanthosis nigricans causes velvety, dark patches that usually appear on the underarms, inner thighs and neck. People with diabetes or obesity are more likely to have them.
• Lentigines are small (2-3mm) round or oval patches that are tan to dark brown
• Lichen planus pigmentosus are grey-brown patches that tend to appear in parts of the body that are exposed to the sun

While some of these patches can look similar to the layperson, a dermatologist can usually tell them apart. To make the diagnosis, the doctor may ask you some questions about your medical history, family history of skin conditions and some lifestyle factors such as how much time you spend outdoors. Your age may also be a factor: freckles and age spots can look like melasma, but freckles tend to affect preteens and teens and fade over time and age spots affect older people. Melasma is the more common cause of brown spots in people aged 20-50. Do tell your dermatologist if you are taking birth control pills or if you are pregnant, as these are known to trigger melasma.

Rarely, your doctor may advise a skin biopsy to rule out other conditions.

Melasma is marked by greyish brown to dark brown patches on both sides (symmetric) of the face, neck or both shoulders and forearms.

Melasma caused by pregnancy or birth control pills usually resolves on its own. In cases where the melasma persists, there are dermatological treatments to lighten or remove the spots—though the spots may come back after some time in some patients.

The best thing you can do to avoid or limit melasma is proper sun protection—wear a good broad-spectrum sunscreen and remember to reapply it as many times as necessary during the day. Sun exposure is among the top causes of melasma in Indian men and women, according to research.

Next, the easiest way to deal with melasma spots could be to wear make-up (cosmetic camouflage), such as a good concealer.

Your doctor could also advise you on using skin‐lightening agents, chemical peels or laser therapy, or depigmenting agents like hydroquinone, retinoic acid, azelaic acid or kojic acid depending on your skin type and the extent of melasma. Other treatments include dermabrasion, CO2 laser and glycolic acid peelings. Check with your doctor to know if you are a good candidate for any of these procedures.