What is melasma?
Melasma is a common yet chronic skin condition, which presents with blotchy, symmetrical, brown colored pigmentation predominantly over areas such as neck, chest, back or upper extremities.
Although melasma has no serious debilitating effects, it takes a toll on the affected individual due to cosmetic reasons. In some severe cases, it can result in psychological body image issues that may lead to social anxiety and depression.
Most commonly affected areas of melasma are forehead, nasal bridge, cheeks and peri-oral region. It tends to appear in areas that are frequently exposed to sunlight, which is why it is seen most often over face, forearms and neck.
Who is at risk for melasma?
Pregnant women, and women in general are more prone to melasma than men. The ratio of affected male to female is approximately 1: 4-20.
Although it can start at any age, melasma is found to occur mostly in between ages 20 and 50.
Fitzpatrick skin types 3-4, i.e. brown skin are more likely to acquire melasma than their fairer counterparts of Fitzpatrick skin types 1-2.
What causes melasma?
The cause of melasma is complicated and poorly understood. As of now it is believed that the hyper-pigmentation is a result of hyperactivity of the melanocytes resulting in excess production of melanin by the pigment cells. The excess melanin is transported through the epidermis to be settled in the dermis layer. In simple words, modified activity of skin pigments results in deposition of melanin pigment in the dermis.
Melasma also seems to have a hereditary component with families tending to pass on the melasma to their offsprings. Study reports that atleast one in three people with melasma has a family member previously afflicted with the same condition.
Hereditary component plus environmental factors together trigger melasma. Some melasma triggers are:
- Sun Exposure: The most important trigger and yet the most easily preventable factor is sun damage. Ultraviolet rays activate melanocytes to produce abnormally large quantities of melanin.
- Pregnancy: In some women, melasma appears suddenly during the second trimester and disappears within a few months after delivery.
- Hormone replacement therapy with estrogen or progesterone may also trigger or aggravate an existing melasma.
- Laser therapy with ablative lasers that burn off the topmost epidermal layer.
- Thyroid disorders
What does melasma look like?
The major presenting symptom of melasma is tiny macules, commonly known as freckles spread over larger brown areas of patches. The distribution is symmetrical on both sides of the face but has poorly demarcated borders. These are found on both sides of the face and have an irregular border.
Distinguishing the type of melasma using a wood lamp is essential for an effective treatment plan. A wood lamp uses UVA1, i.e. black light to distinguish the layers affected by the melasma.
It is even more distinctly visible under black light as well-demarcated, dark brown colour pigmentation. In most cases, epidermal melasma has a good recovery prognosis with treatment.
Unlike epidermal melasma, dermal melasma doesn’t get more prominent under black light. It has poorly defined border with a lighter brown color. Limited improvement can be achieved by treatment.
In most cases, both epidermal and dermal type of melasma tend to occur. Treatment shows partial to significant improvement depending upon the predominant type of melasma.
How can melasma be diagnosed?
Diagnosis of melasma is mostly done clinically based on the appearance of skin pigmentation. Sometimes, a differential diagnosis needs to be done, as pigmentation can be a result of many underlying causes apart from melasma.
Some other causes of hyperpigmentation may be acne scars, lentigo, postinflammatory hyperpigmentation, drug-induced, fungal dermatitis, naevus of ota , etc.
Rarely, skin biopsy needs to be done in abnormal appearing raised pigmented areas to rule out malignant conditions.
Scales such as Melasma Area and Severity Index (MASI) are occasionally used to grade the severity of melasma, particularly for research purposes.
What are the treatment options for melasma?
Despite being a very common condition affecting millions of people around the globe, melasma treatment has not been perfected to say the least.
Most patients respond very slowly to treatment, which can be widely attributed to poor patient compliance. The longer the duration of the melasma, the poorer is the treatment response.
Treatment should also be carefully planned as aggressive approach in patients with sensitive skin may lead to contact dermatitis or hypopigmentation.
Treatment should be multifaceted with a combination of active treatment and prevention via protective measures.
1. Hydroquinone: Hydroquinone should be applied over pigmented areas every night for 8-16 weeks till significant improvement is achieved. Long term continued treatment or treatment with doses higher than 4% is not recommended as it can have adverse effects such as permanent hypopigmentation or in some cases orchonosis, which is a bluish discoloration of the skin.
2. Ascorbic Acid (Vitamin C): A potent effective treatment option for melasma with minimal side effects.
3. Azelaic acid cream: It is less potent in comparison to hydroquinone but is safe to use long term as well as in pregnancy.
4. Topical steroids with hydroquinone may rapidly fade melasma. It has the added benefit of preventing side effects of hydroquinone such as irritant contact dermatitis.
Other topical treatment options that are not widely used but potentially effective are:
- Kojic Acid
- Cysteamine cream
- Tranexamic Acid
- Soybean extract
In addition to nightly topical treatments, occasional chemical peels to exfoliate the epidermis and increase skin turnover may improve melasma. Some effective chemical peels include:
- AHA/BHA peels such as glycolic acid, salicylic or lactic acid peels in low concentrations
- Topical retinoids in 0.5% concentration increase cell turnover time and peel off the epidermis.
A combination approach with hydroquinone, retinols and hydrocortisone has been found to be effective in almost 75% of melasma patients. Continued use for 12 to 16 weeks is needed to see significant improvement.
High-tech devices to treat melasma
Treatment with high-tech devices such as fractional laser and CO2 lasers should be avoided as they worsen the pigmentation. Even skin microneedling, also known as vampire facial may worsen melasma.
Q-switched Nd:YAG lasers and Intense Pulsed Light(IPL) may have some efficacy in melasma treatment but should be used with caution.
Apart from the topical treatments, triggers should also be avoided such as oral contraceptives, sun exposure and unnecessary facial lifting procedures. Among these, sun protection with a high SPF index is crucial to prevent further aggravation of melasma. Sunblock should be applied frequently every 3-4 hrs, every day and year round.
Long Term Prognosis of Melasma
Melasma can be treated but unfortunately it is a chronic, recurrent condition. Even after a successful treatment, it may recur following any triggers such as sun exposure or pregnancy. Melasma is currently being extensively researched and new oral treatments for melasma are under clinical study.