Melasma is a form of skin hyperpigmentation, most commonly seen and most likely to develop in pregnant women and women in their reproductive years between 20 and 50 years of age, who have olive or darker skin tones from Latin, Asian, Hispanic and Middle Eastern descent. There are no physical symptoms other than the hyperpigmentation and it is rarely seen in males, no more than 10% of cases.
The triggers for this condition are thought to be daily or intermittent exposure to ultra-violet light, where heat may also be an instigating factor; or hormonal influences as found in pregnancy, hormonal therapies and the using of oral contraception which involve oestrogen and progesterone sensitivity. The treatment of the possible hormonal causes is difficult due to being unable to remove the instigating hormonal factors. When melisma occurs in pregnant women, it is also known as the ‘mask of pregnancy’ or chloasma. Stress and thyroid disease may also cause melasma, as can certain skin products which cause irritations. There may be a genetic component to melisma as people whose close relatives who have had this condition are more likely to develop it themselves.
Its appearance is that of discoloured patches in shades of brown, tan and blue-grey on the face, usually on the upper cheeks, upper lip, forehead, chin or jawbone area, where the patches are symmetrical, with matching marks on both sides of the face. Less commonly, patches may appear on a person’s arms and neck.
There are four types of Melasma as follows:
- Epidermal melasma has excess melanin seen in the superficial skin layers.
- Dermal melasma has the presence of melanophages throughout the dermis – these cells ingest melanin.
- Mixed melisma includes both the epidermal and dermal types of cells and is the most common form.
- Excess melanocytes present in the skin of dark-skinned people.
Melasma is different from normal hyperpigmentation or darkening of the skin caused from acne scar tissue, freckles that grow into larger sun spots or patches caused by eczema or psoriasis. Pigmentation caused by acne, sun or skin rashes, stimulates the production of melanocytes, making excess pigment in the lower levels of the skin, which then shows up on the skin as discoloured areas ie malfunctioning of the melanocytes causes them to produce excess colour.
The treatment of these two different skin conditions differs quite radically. Darker skinned people have more melanocytes that people with lighter skins, hence their tendency to develop melasma, as ultra-violet rays affect the melanocytes that control pigmentation.
Melasma is seen as symmetric blotchy hyperpigmented patches on various facial areas such as the cheeks, bridge of the nose, forehead, chin and above the upper lip. It can appear on other parts of the body that have been exposed to the sun such as the neck, shoulders and forearms. It is often worse in summer than in winter which indicates that heat may be an instigating factor such as sun bathing or even infra-red light in a sauna.
Melasma can last for years, and even for the duration of a person’s life, as not all treatments work for everyone and it may come back even after successful previous treatments.
Diagnosis and Treatments for Melasma
Generally a visual examination is sufficient to diagnose melasma. In some uncertain cases a Wood’s lamp examination may be necessary – this special light is used to check for bacterial and fungal infections and it is able to determine how many layers of skin are affected by melasma. Occasionally a biopsy may be performed should the condition seem serious.
When melasma occurs in pregnant women and those who take contraception pills, then this condition may simply disappear on its own once the pregnancy is over and the taking of contraception pills is stopped.
Certain creams, as well as topical steroids, can be prescribed to lighten the skin. Other options are dermabrasion, microdermabrasion or chemical peels which strip away the top skin layers. There is no guarantee that melasma won’t reoccur and certain practices may need to be followed up.
The one definite factor is to minimise sun exposure by using sunscreen products that cover UVA and UVB with a SPF of 50 or more, and reapplying these every two hours while being exposed to sunlight, as well as wearing a wide-brimmed hat and sunglasses when outside. Protective clothing should be worn if you have to be in the sun for extended periods of time.
If medication has been prescribed, then it is of paramount importance to take this as prescribed.
To cover facial pigmentation makeup products that contain iron oxide will help to block out visible light rays.
A common first line of treatment is the use of an over-the-counter 2% Hydroquinone cream, lotion or gel which is applied directly to the discoloured patches in order to lighten and fade the colour of the patches. These should be applied to the patches twice a day and in the morning a sunscreen application should also be applied over the hydroquinone cream. This treatment works best on epidermal melasma as the pigment is close to the skin’s surface. Treatments must be discontinued during pregnancy due to the risk of harming the foetus, and cosmetic creams can be used to cover the patches during pregnancy.
Hydroquinone (hydroxyphenolic chemical) blocks a step in a specific enzyme pathway involving tyrosinase, the enzyme that converts dopamine to melanin which gives the skin its colour.
High concentration Hydroquinone creams may cause skin irritations if used for prolonged periods over many months – this condition is called ochronosis where the skin actually darkens permanently due to the use of a Hydroquinone concentration above 4%. This condition is more common in areas of Africa where Hydroquinone concentrations of 10-20% may be used. At the first sign of ochronosis the treatment should be discontinued.
Other treatments which require a physician’s prescription are Corticosteroids and Tretinoin which are also in cream, lotion or gel forms. Combination triple creams contain Hydroquinone, Corticosteroids, and Tretinoin in one. Dermatologists may prescribe non-hydroquinone alternative treatments such as topical Azelaic Acid, Kojic Acid or other chemicals which also lighten the skin.
Azelaic Acid is very effective but not as good as 4% Hydroquinone. Possible minor side effects from these alternate treatments may include itching, redness, scaly dry patches and a temporary burning sensation.
If topical medications do not work, then other procedures may be recommended such as chemical peels, dermabrasion, microdermabrasion, laser or light therapy. There are side effects from some of these treatments but a dermatologist will point out the risks associated with these procedures. The candidates for these types of treatments are those who have uneven pigmentation and/or actinic keratoses.
The specific type of chemical peel will be decided by the physician. 30-70% Glycolic Acid peels are common and sometimes a mixture of 10% Glycolic Acid and 2% Hydroquinone will be used.
Dermabrasion and microdermabrasion will improve melasma after a few treatments. Fine diamond chips or aluminium oxide crystals are used in a vacuum suction to exfoliate the skin and a treatment can last from a few minutes to an hour. The best results are seen when this system is used together with sunscreen and Hydroquinone creams. Occasionally this treatment may worsen the melasma and there is no guarantee that it will be successful. As this treatment is considered to be a cosmetic treatment it may not be covered by medial aid.
Laser and light therapies generally produce temporary results and in some case may worsen the condition. Treatments need to be repeated often in order to see effective results
To ensure that the above treatments work to their best advantage it is imperative to limit sun exposure, use sun protection by using sunscreen products that cover UVA and UVB rays, with a high SPF factor of 50, wear sunglasses to protect eyes, and always wearing a wide-brimmed sun hat. Ideally the best prevention is to avoid exposure to sunlight and people who have a family history of melasma must take extra precautions to prevent the onset of melasma.