The light side of pigmentation

Hyperpigmentation is the darkening of areas of skin compared to the surrounding skin colour leading to uneven skin tone or large darker patches. It occurs when melanocytes are stimulated to produce increased pigment called melanin. Melanocytes can be stimulated by sunlight, hormones, trauma, inflammation, medication and a constantly growing list of other factors. It was recently discovered that vascularisation (increase in blood vessels) also has a role to play in melanocyte stimulation and hyperpigmentation.

Hyperpigmentation is a common and intensely distressing condition. The commonest forms seen are melasma, solar lentigenes (sun spots) and post inflammatory hyperpigmentation (PIH).

What causes hyperpigmentation? – new evidence!

Melasma and sunspots mostly occur on sun exposed areas, particularly the face, while PIH can occur in any area of skin trauma or skin conditions like acne, eczema or insect bites.

All forms of hyperpigmentation worsen with sun exposure. It is well established as the greatest contributor, with the condition worsening during summer and improving in winter when ultraviolet exposure is less intense.

Melasma is also strongly influenced by genetic and hormonal factors and is often precipitated by pregnancy or the use of the contraceptive pill.

The influence of other environmental factors is only recently being examined, and other causative factors have now come to our attention as contributing to skin ageing and hyperpigmentation.

The solar energy spectrum is composed of ultraviolet radiation (A, B and C), visible light and infrared. The visible light spectrum is the light that we see. It has longer wavelengths than ultraviolet A and B and therefore actually have a deeper penetration into the skin, though they have never been regarded as potentially harmful.

Recent studies have found that visible light stimulates melanocytes to produce pigment. This is especially significant in darker skinned individuals and it seems that repeated long term exposure to visible light may cause hyperpigmentation. In addition, visible light may also cause inflammation and induce reactive oxygen species causing DNA damage, though it has not yet been established as a cause of skin cancer.

Important to note that most traditional sunscreens do not adequately protect against visible light. Fe oxide in sunscreens and antioxidants offer protection from visible light.

Infrared or heat represents the longest wavelength of solar energy and hence penetrates even further than visible light. IR activates matrix metalloproteinase and causes the breakdown of collagen causing skin ageing. Infrared also causes hyperpigmentation by inducing inflammation and vascularization (production of blood vessels). There is currently no effective way of protecting against infrared and only topical antioxidants have shown to offer some protection.

Traffic related air pollutants including a harmful form of ozone called tropospheric ozone and polycyclic aromatic hydrocarbons cause the formation of free radicals which depletes our skins antioxidant reserve. This leaves the skin vulnerable to further insult including DNA mutations and melanocyte stimulation.

Treatment for hyperpigmentation

Hyperpigmentation is treated with a combination of topically applied creams, and skincare procedures like chemical peels and dermal needling.

A complete treatment regimen should:

  • Protect against factors that cause melanocyte stimulation
  • Inhibit the production of melanin by inhibiting the enzyme tyrosinase
  • Improve the turnover of cells that have accumulated pigment

Maintenance treatment is critical to ensure that results are lasting as hyperpigmentation should be seen as a chronic condition that requires constant management.

The gold standard skin lightening agent is hydroquinone which has come under scrutiny as it was used to lighten skin generally, not just for treating hyperpigmentation.

Hydroquinone works by inhibiting the enzyme tyrosinase. This medication can be prescribed where appropriate by a dermatologist in various combinations and works well when used responsibly.

Kojic acid is an effective and well studied skin lightening agent. It is an ingredient in numerous creams and generally well tolerated

Neoretin Booster Serum is a lightweight serum containing Kojic Acid and other active ingredients which inhibit melanin synthesis.

SkinCeuticals Metacell Renewal contains Kojic Acid and other active ingredients to target the early signs of ageing and hyperpigmentation.

NeoStrata Enlighten Pigment Gel contains Kojic Acid, Liquorice extract, citric acid and multiple other active ingredients to target hyperpigmentation.

Arbutin is a glycosylated hydroquinone extract and has been considered one of the safest and most effective skin lightening agents. Its effects may also be optimised when combined with other substances like vitamin c, liquorice, glycolic acid and kojic acid.

Arbutin inhibits the enzyme tyrosinase decreasing the production of melanin pigment.

The active ingredient is slowly released making it suitable for those with sensitive skin.

Obagi Nu-Derm System

The Nuderm system combines Arbutin and exfoliating ingredients to inhibit melanin production and remove cells containing pigment. Arbutin is a smaller molecule that penetrates deeper into the skin reaching the basal layer of the epidermis and inhibiting the enzyme tyrosinase.

Obagi C Clarifying Serum combines 10% Vitamin C and Arbutin to protect against sunlight and environmental aggressors and inhibit production of melanin. This product targets early ageing and hyperpigmentation.

Vitamin C is a potent antioxidant which indirectly inhibits the enzyme tyrosinase leading to decreased melanin production

The anti inflammatory effect reduces cell injury and pigment production.

SkinCeuticals CE Ferulic and SkinCeuticals Phloretin CF are patented combination antioxidant formulations. Vitamin C is combined with other antioxidants for a potent synergistic effect that protects against ultraviolet light and visible light and offers some protection against infrared (IR) and air pollutants.

Obagi Professional C serum 10%, 15% and 20%.

The Obagi Professional C range contains different concentrations of Vitamin C to suit different skin sensitivities.

Ellagic acid

Is a natural phenol antioxidant that inhibits the transfer of melanin to skin cells.

SkinCeuticals Advanced Pigment Corrector contains ellagic acid, niacinamide , vitamin and salacylic acid. It lightens dark spots by gentle exfoliation and prevents the formation of new pigment spots.

Tranexamic acid reduces pigmentation by its effect on the plasminogen activator pathway.

SkinCeuticals Discoloration Defense

Combines tranexamic acid (inhibits the UV induced production of melanin by melanocytes), Kojic acid , niacinamide and HEPES which work synergistically to inhibit melanin production and remove epidermal cells containing pigment.

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Note from Dr. Kesiree

HYPERPIGMENTATION should be regarded as a chronic condition that needs to be constantly managed. Be consistent with your treatment regimen. Treatment protocols generally combine intense phases of prescription treatment and procedures with maintenance regimens.

No treatment regimen for hyperpigmentation would be complete without strict daily sunscreen use.

Book an appointment with your dermatologist or skincare professional for advice on how best to treat your hyperpigmentation