Unique Features of Melasma

Melasma is a skin condition marked by darkly discolored patches that appear most commonly on the face. It can appear as a small spot or take up large areas. Regardless of how small or large, melasma is emotionally distressing because it changes facial appearance. Melasma is common among many different ethnicities.^[1,2] There are many therapies directed toward treating melasma including hydroquinone, retinol, laser treatments and the use of emerging botanical treatments. 

Good questions to ask are:

• Is all melasma created equal?
• Will your melasma improve with the same treatments that helped a friend?  

The short answer is that not all melasma is created equal, and what helped a friend may not help you. It depends on what is triggering the discoloration. Here are a few nuances that you should consider. 

Is My Melasma Really Melasma, or Is It Something Else? 

There are many conditions within dermatology that can look similar to melasma to an untrained eye. Some examples include birthmarks, sunspots (lentigines), and even melanoma skin cancer. It is very important that persistent dark spots on the face be evaluated by a healthcare provider to rule out skin cancer before thinking about treatments to get rid of the pigment. 

What Can Trigger Melasma?

Several factors are associated with melasma.

Hormones play an important role in melasma. Studies show that female sexual hormones, such as estrogen and progestins, are important in the development of melasma. Melasma is more common in women and is common in pregnancy.^[1,2] Further support for the hormonal triggers for melasma is that the use of oral contraceptive pills is associated with its development.^[3,4] Changes in the levels of the thyroid hormone have also been associated with melasma.^[5]

Ultraviolet light can stimulate the skin to produce more pigment, leading to melasma.^[1,2,6] Both ultraviolet light type A and type B from the sun are involved in triggering the formation of melasma.^[1]

Family history (i.e. the occurrence of melasma in other family members) plays an important role.^[7,8] Studies have estimated that family history was reported in at least 10% and even up to 48% of those with melasma.^[8,9] 

Is My Melasma Occurring at the Skin Surface? 

Yes, but melasma can be found at several different skin depths and this can affect the success of treatments.^[10] It may be helpful to think of melasma as occurring in two separate depths of skin, although many people will have an overlap between the two forms:

1. Epidermal melasma: skin pigment is overproduced in the more superficial layer of the skin known as the epidermis. Epidermal melasma is more likely to improve with treatment.
2. Dermal melasma: pigment is found in the deeper layers of the skin known as the dermis. This type of melasma is harder to treat because treatments may have a harder time penetrating to greater depths in the skin where they would be active against melasma.^[11]  

Summary

Melasma can be psychologically distressing and is challenging to treat. It is important to understand that several different factors affect the development of melasma.  Understanding the unique causes and variations in each individual is important before delving into treatments.