MELASMA/SUN DAMAGE/HYPERPIGMENTATION
Melasma is a common acquired skin disorder that presents as a bilateral, blotchy, tan, or dark brown skin pigmentation. It was previously called chloasma, but this derives from the Greek meaning ‘to become green’, the term melasma (brown skin) is now preferred. It was also known as the ‘mask of pregnancy’.
Melasma is more common in women than men, with an onset typically between the ages of 20-40 years. Melasma is more common in people who easily tan or have naturally brown skin according to Fitzpatrick skin types (you can see the Fitzpatrick scale in my clinic). It is a lot less common in people with fair skin. Darker skin naturally has more active pigment- producing cells, and melasma appears when these cells become hyperactive and produce too much pigment in certain areas of the skin. The mechanism is similar to the cause of brown age spots and freckles but melasma patches tend to be larger.
The cause of melasma is complex, the pigmentation ultimately results from the overproduction of melanin by the melanocytes (pigment cells), either taken up by keratinocytes or deposited in the dermis.
Factors implicated in the development of melasma include;
· Family history – 60% report affected family members.
· Sun exposure – UV & visible light promote melanin production.
· Hormones – pregnancy and the use of estrogen/progesterone – containing oral contraceptives, implants and hormone replacement therapy are implicated in one quarter of women affected. Thyroid disorders can be associated with melasma.
· Medications and scented products may cause a phototoxic reaction to trigger melasma.
· Researchers are currently examining the roles of stem cell, neural, vascular, and local hormonal factors in promoting melanocyte activation.
The clinical features of melasma are bilateral, asymptomatic, light to dark brown macules or patches with irregular borders. Melasma can be separated into epidermal, dermal, and mixed types depending on the level of increased melanin in the skin, with mixed melasma being the most common.
Other disorders that may resemble melasma clinically include;
· Post inflammatory hyperpigmentation.
· Solar lentigo and freckles.
· Acquired dermal macular hyperpigmentation.
· Drug induced hyperpigmentation.
TREATMENT OF MELASMA
The first step is confirming with a dermatologist that it is indeed melasma. Then trying to determine the cause. If the underlying cause is not addressed, then any treatment is unlikely to be successful. Melasma usually requires a combination of measures.
· General measures are year-round, life-long, sun protection, SPF50. There are 2 main types of sunscreen (there is more detail in my SKCIN & SPF blog) but for melasma you want to choose a non-chemical blocking sunscreen because that will stop all the light and different wavelengths from coming through. Chemical sunscreens do not offer the same protection for melasma and in some cases can trigger allergic reactions that make melasma worse. Back your SPF up with a hat designed for added sun protection if you are going to be outside for an extended period.
· Topical therapy – with the most successful formulation being a combination of hydroquinone (a tyrosinase inhibitor, tyrosinase is an enzyme found inside melanosomes which are synthesized in the skin melanocytes) & tretinoin (see my retinoids blog).
· The use of topical retinols and retinoid treatments (for more info see my retinol blog) help to speed up your body’s natural cell turnover process. This may help dark patches clear more quickly than they would on their own.
· Hydroquinone which works by blocking melanin production should only be used under a dermatologist’s care, and only on the darkened areas of the skin. Some dermatologists may recommend chemical peels, laser treatments and skin micro needling, but these need specific care, one size does not fit all and for some it may help whereas in others it may make it worse.
· Superficial chemical peels are the most likely of the above to be used and can be used with caution, but deep peels carry a risk of worsening melasma or causing post inflammatory hyperpigmentation. Patients should be treated with a tyrosinase inhibitor such as hydroquinone. Superficial epidermal pigment can be peeled off using Alpha hydroxy acids or Beta hydroxy acids.
· Whereas micro needling, intense pulsed lights and lasers carry a high risk for relapse and the disease becoming more resistant to treatment and would require expert use, if at all.
Melasma can be frustrating to treat. The outcome for melasma is that it is slow to respond to treatment especially if it has been present for a long time. In those who get a good result from treatment pigmentation may reappear on exposure to summer sun. The need for lifelong sun protection every day cannot be over emphasised.
AT HOME TREATMENTS
There is more you can do on your own to help your skin heal and prevent future damage. In addition to reducing sun exposure.
1. Establish a good cleansing regime. Environmental pollution can contribute to melasma, airborne pollutants bind to the skin and corrode the protective surface making it weaker and more susceptible to sun damage. Cleanse your skin every morning and double cleanse at night with a pharmaceutical/cosmeceutical targeted skin care that will thoroughly remove particulate and help protect the skins barrier.
2. Combat skin stress with antioxidants. Vitamins C & E can help heal damage from sunlight. Using a serum that contains these will improve skin health and ward off the harmful effects of sun exposure.
3. Moisturise your skin regularly. Use a toner/moisturiser in your skin care regime morning and night to restore the lipid barrier of the skin, protecting it from damage.
4. Be patient. Even with treatment it may take months rather than weeks for melasma to clear up.
5. Be diligent. Melasma will be quick to return if you are not careful about sun protection. Long term maintenance requires an ongoing commitment to protecting your skin.
HYPERPIGMENTATION
Yes, melasma is a form of hyperpigmentation but I felt it required most of this blog on its own with a quick address to other causes of hyperpigmentation as an addition.
Like melasma other causes of hyperpigmentation are usually also a harmless condition in which patches of the skin become darker in colour than the normal surrounding skin. The darkening also occurs just as described in melasma when there is an excess of melanin, the brown pigment that produces skin colour. However, melasma and sunspots are more likely to affect areas of the skin due to sun exposure, there are other types of hyperpigmentation that form after an injury or skin inflammation, such as cuts, burns, acne, or lupus. Again, people with darker skin are more likely to develop post-inflammatory hyperpigmentation. Where melasma mostly affects women, hyperpigmentation affects men and women equally.
Post – inflammatory hyperpigmentation occurs when there is inflammation in the epidermis. This inflammation stimulates melanocytes to increase melanin synthesis and to transfer the pigment to surrounding keratinocytes (epidermal melanosis) if the basal layer is injured, melanin pigment is released and subsequently trapped by macrophages in the papillary dermis (dermal melanosis).
The treatments for hyperpigmentation of this type must be carefully thought out as we do not want to aggravate it by causing more injury or inflammation.
Home care as above for Melasma and always SPF every day! Even when at home.
