skin colour

Hi. My underarms are really dark. I used to use hair removal creams and reacted to it. I cannot wear sleeveless clothes. Kindly advise as how i can get rid of the dark patches.

[Dr_Aparna]

Hi,
Any irritation of the skin in this area, either due to shaving/waxing/creams may cause the skin to darken.
This can be due to skin thickening at this site in response to the irritation or it could be due to the traumatizing of the melanocytes in this region, causing them to produce excess amounts of melanin.

Hyperkeratosis is a thickening of the skin that occurs in women with brown skin. It is due to excessive accumulation of keratin in the outer layers of the skin. Thickening of the skin protects it against rubbing, pressure and irritation. Hyper pigmentation accompanies this type of hyperkeratosis.

Topical creams that contain as the active ingredient salicylic acid, alpha-hydroxy acid (lactic or glycolic acid), urea, or tretinoin can be applied on the affected areas, which aim at softening the keratin and removing the thickened skin.
Along with this you can use skin lightening agents like Hydroquinone 2-4%, which acts as a bleaching agent.

Any improvement can be seen only after 2-4 months of consistent use.
ref:http://www.brownskin.net/hyperkeratosis.html