Extremely Dark underarms and groin area

I have had this problem since i was a teenager; i was hospitalized for almost a year in which time i put on quite alot of weight and after being bedridden did  these dark areas appear. I am brown skinned and generally have quite healthy skin except on these areas. I have tried lighting creams, bleaches and even Retin A and it has not helped or made any difference. I have never been comfortable with wearing sleeveless because my underarms have very visible extremely dark patches. I'm 27 years old and i really want to be free of this. Please help

[Bhupinder Kaur, MD]

Hello,
It is very common for the folds of skin to become dark in overweight people because of the continuous sweating in the area. The other possibility that needs to be ruled out is acanthosis nigricans.It presents as symmetrical, hyperpigmented, velvety plaques mostly in the folds of skin. It is not itchy and is characterized by hyperpigmentation. My sincere advice would be to consult a dermatologist and get it evaluated as treatment is diagnosis specific.
I hope it helps. Take care and please do keep us posted in case you have any additional doubts. Kind regards.