Pigmentation means discolouration of the skin. There may be increased pigmentation (Melasma, solar melanosis, freckles, Drug induced pigmentation etc.) or decreased pigmentation (healing lesions, pityriasis alba, leprosy etc.) or complete absence of pigment (Vitiligo)
Common pigmentary disorders
- Melasma: hormone related, dark, mottled pigmentation on the cheeks, nose, forehead, and chin. More common after pregnancy and in women on contraceptive pills and certain other drugs. Can also be seen in men
- Birthmarks: Naevus of ota, beckers naevus, congenital melanocytic naevi, junctional naevi, compound naevi etc. Commonly known as moles or birthmarks and are present since childhood.
- Solar melanosis: Pigmentation on areas exposed to sunlight
- Freckles: spots of pigmentation on cheeks and face due to sun damage. Runs in families and more common in fair-skinned people.
Diseases associated with pigmentation
- Post inflammatory pigmentation: pigmentation seen after an active skin disease is resolving, ex: after acne(pimples), seborrheic dermatitis, skin infections, psoriasis etc.
- Lichen planus pigmentosus: Bluish gray pigmentation on the sun exposed areas with deep level of pigmentation
- Acanthosis nigricans: due to thickening of the skin, over nape of the neck, sides of the forehead, axilla and groin,usually associated with weight gain and insulin resistance states.
Drug induced pigmentation
Several medicines can cause pigmentation either by direct deposition of the medicines in the skin or reaction of the skin to the medicines.
Sunscreens form a very important part of the treatment by preventing formation of new pigment and preventing sun damage (especially in melasma, post inflammatory pigmentation and freckles)
- Topical medicines: Medicines to remove increased pigment like glycolic acid, kojic acid, pine bark extract, liquorice etc in the form of creams
- Chemical peels: These are enhanced preparations to speed up the process of pigment removal and are controlled peeling techniques of the skin performed under the supervision of a dermatologist. Advanced peels with a combination of retinol, kojic acid, glutathione, vitamin C, glycolic acid, salicylic acid, mandelic acid, lactic acid etc are used.
- Lasers: To remove deep-seated pigment and birthmarks. Conditions like naevus of ota can be completely treated by lasers. Most commonly used is the Q-switched Nd:YAG laser. Pulsed dye lasers and carbon dioxide lasers are also used.