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Melasma in an Asian Woman |
Melasma is another skin pigmentation disorder that can
cause distress for people with brown skin. Like post-inflammatory hyperpigmentation
(PIH), melasma results from functional problems with cells that produce
and contain the melanin pigment. This dysfunction results in the appearance
of irregular brown or grayish-brown marks on facial skin that is normally
clear.
In melasma, the dark spots and patches usually affect
the nose, cheeks, forehead, upper lip and chin in three different patterns.
The most common pattern tends to affect the central portion of the face
including the cheeks, forehead, chin and nose (centrofacial type). The
second form affects the cheeks only (malar type). The least common form
appears only on the jawbone (mandibular type). Although melasma tends
to be concentrated on the face, it does sometimes occur on other parts
of the body, such as the forearms and neck.
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Close-up of Melasma |
Melasma can occur in all skin types and in people of
all racial and ethnic groups, but is most common in women with brown
skin who are between the ages of 21 and 40. It is sometimes referred
to as the “mask of pregnancy” because it occurs commonly
during pregnancy and in women who take oral contraceptive pills. Furthermore,
people living in areas of intense and prolonged sunlight (Asia, Africa,
Latin America and the Carribean) are more susceptible to developing
melasma.
Although the exact causes of melasma remain unknown,
common factors linked to the disorder include pregnancy, use of oral
contraceptives (BCPs), hormone replacement treatments (estrogens), hormonal
abnormalities, as well as a family history of melasma. Sun exposure
is also a significant factor in the cause of melasma. Some dermatologists
also believe that melasma could be stress-induced, since the release
of melanin is controlled by hormones which are easily influenced by
stress. Additionally, cosmetics and some types of anti-seizure medications
have also been linked to melasma.
There are three forms of melasma:
- Epidermal - A treatable form that occurs in the upper layers of the skin.
- Dermal - A form that occurs within the deeper layers of your skin and is therefore untreatable.
- Mixed type - A combination of the previous two forms and is therefore partially treatable.
When melasma affects women due to pregnancy, it may resolve within a few months after delivery and treatment may not be necessary. There are, however, many cases in which the disorder persists indefinitely.
In general, the condition usually develops slowly and
symmetrically, and can last for many years with worsening in the summer
and improvement during the winter. Even when treated successfully, melasma
often recurs, especially when the skin is exposed to the sunlight.
For all individuals with melasma, it's imperative to
wear a broad-spectrum (UVA plus UVB) sunscreen daily; avoid the sun
when possible; and wear protective eyewear, caps, hats and clothing.
You should select a SPF sunscreen that contains either titanium dioxide
or zinc oxide, which will provide a physicial barrier between your skin
and the sunlight. When melasma develops in response to hormone treatment,
either oral contraceptives or hormone replacement therapy, patients
should consult with their physicians to discuss discontinuation of the
hormones.
Treatment
There are several medications available for the treatment of melasma.
These would include the medications previously discussed for the treatment
of PIH (hydroquine, tretinoin (Retin-A),
azelaic acid, glycolic acid, as well as chemical peels and microdermabrasion)
and the cream, Tri-Luma.
Differences between Melasma and PIH
Although PIH and melasma are very similar conditions, in that they both
cause an increase in the pigmentation of the skin, there are a few key
differences. While PIH often heals spontaneously, melasma tends to persist
for prolonged periods or time. PIH may occur on any area of the body,
whereas melasma usually occurs on the face, which is exposed to the
sun. While PIH is usually distributed between the sexes, melasma tends
to predominate in women. PIH is preventable while melsma is difficult
to prevent. Overall, the symptoms and treatments of these pigmentation
diseases tend to be very similar.
