-What is the basic structure of the skin and what is responsible for giving it a colour?
Skin is the largest organ of the body. It is made up of two layers, the upper ‘epidermis’ and the lower ‘dermis’. The epidermis and the dermis are further divided into other layers.
The lower most layer of the epidermis is known as the basal layer and it contains organelles called ‘melanosomes’. These melanosomes contain cells called melanocytes which produce a pigment called ‘melanin’. The colour of skin depends mainly on this melanin and the amount of melanin present in the other layers of the epidermis. The thickness of epidermis and vascularity of the epidermis are other factors affecting the colour of skin
What are the causes of hyperpigmentation (increase in skin pigmentation)?
Hyperpigmentation may either be due to increased melanin deposition in the epidermis or dermis.
Epidermal pigmentary disorders respond well to treatment while dermal pigmentation may take a long time to lighten.
Melasma : Seen as brown patches on the face, it is more commonly seen in females. It occurs due to hormonal changes in the body. The pigmentation increases on sun exposure.
Peri-orbital melanosis : Also known as ‘dark circles’ may be heriditary, due to stress or eye strain
Freckles and Lentigenes : These are tiny black spots on the face and are genetic in origin.
Photomelanosis : This is increased pigmentation due to sun exposure. The pigmentation occurs on exposed skin, commonly on the face, neck and the back. The pigmentation may be patchy or as diffused darkening of the exposed skin.
Sun burn (tan) : A condition commonly encountered in fair skinned people due to excessive sun exposure.
Post inflammatory hyperpigmentation : It may be seen in the following cases:
Seen after healing has occured, like in acne, eczemas, contact dermatitis etc.
Drug induced pigmentation.
Pigmentation due to cosmetics especially those containing fragrance.
Systemic disease such as Addison disease, liver disease, pregnancy, pituitary tumours.
What is the treatment for hyperpigmented disorders?
Determining the cause of the hyperpigmentation is important in selecting the best approach for treatment. Hyperpigmentation is treated with the application of topical creams, chemical peels, lasers. Patients should avoid the sun by using sun-protective clothing and sunscreen to decrease the likelihood of pigmentary changes induced by UV light.
-What is a chemical peel?
Chemical peeling is application of a solution/gel on the treatment area for a particular time period. It is an office procedure. It does not require any hospitalisation. After properly studying the skin type and its sensitivity, the dermatologist decides on the type of peeling agent and their concentration. The skin is first cleansed. The peeling agent is then applied gently onto the lesion or on the full face till the ‘end point’ is achieved.
During or shortly after the procedure, the patient might experience warmth or stinging sensation for a few minutes. The procedure can be repeated after 2- 3 weeks.
-What are the latest peels used in dark skin with proven efficacy?
While Glycolic acid, TCA, Salicylic acid, Jessner’s, Baker Gordon’s peels are being used since a long time, newer combination peels are now commonly being used for hyperpigmantation as well as for anti-ageing skin treatments.
Nomelan Fenol : It is a Solution containing phenol, trichloroacetic acid, retinoic acid, phytic acid and a mixture of hydroxy acids (glycolic, ascorbic, salicylic, and mandelic). It is used to treat Acne, Post Inflammatory Hyperpigmentation & Facial Melanosis. A peel is repeated every 3 weeks & a total of 3-5 sessions are done to achieve good cosmetic results. The depth of the solution will depend on the applied layers. For dark skins (phototype IV-VI) one should not apply more than 2 layers at a single peel session. The end result is a renewed and bright complexion with homogeneous skin colour and texture.
Arginine & Lactic acid combination peel : It is used to treat peri-orbital melanosis. Arginine is an Amino Acid derived from Brown sugar. It stimulates protein synthesis & has an anti-inflammatory action with moisturising effect. It is a large molecule, hence there is no irritation even in thin skin areas such as under eyes. It is safe in patients with sensitive skin. Lactic Acid is derived from fermented milk. It helps maintain skin pH and also useful in adjusting the pH of formulations. It moisturises skin as is the skin’s own natural moisturiser.
6-8 sessions repeated at biweekly intervals causes significant reduction of dark circles.
Retinol peel : A combination of 10% ascorbyl 2-glucoside, 15% lactic acid, 4% retinol & 1 % retinaldehyde available as Retises CT peel is used for photoageing, uneven skin tone, fine lines, open pores & stretch marks. It removes dead cells, causes cell renewal, stimulates collagen synthesis & increases natural moisturising factors of the skin.
-Why Combination peels?
They are done to complement the efficacy of different ingredients, to improve the safety of formulations and to increase the range of action of a single ingredient.
Side effects are rare and seen as post inflammatory hyperpigmentation and scarring .These occur only if the patient selection is improper or if the method is wrong or if there is post peel sun exposure.