Acanthosis nigricans, is the name that is known to darkening that can occur mainly in the neck, armpits, knuckles, elbows and crotch. This occurs because the body's cells can not absorb insulin secreted by the pancreas, leading to this body to secrete increasing amounts and the skin is affected.
The people who are most likely to develop are:
Overweight and obesity
Women with polycystic ovary syndrome.
Patients with Hypothyroidism
People with diabetes
People who suffer from hypertension or acute stress.
Should go to a given symptoms that occur in the skin dermatologist, however, an endocrinologist would be more appropriate to offer a deeper treatment. You can only reduce stains correcting your body's resistance to insulin, and this can only be achieved through diet, physical activity and in very specific cases with medication. Remember that skin cells are constantly renewed so as advance treatment color and appearance will normalize. It is important to note that treatments to remove stains and whiten skin can help eliminate it, however, since it is an internal problem of the skin is likely to reappear.
Tips
Avoid using depilatory creams to remove underarm hair as they have acids and chemicals that can aggravate the dark in that area.
Avoid using the razor, because skin damage. It is much better waxing or those methods that remove hair from the root.
Try to wear loose clothing and "breathable" in the underarm area.
Wash armpits properly with soap and water. Poor hygiene causes unattractive shader that due to the accumulation of dirt and oils.
Make a mixture of honey, milk powder and lemon juice into a paste. Then, apply on the skin of the armpits. Leave it on for 15 minutes and rinse properly. Follow this treatment several weeks and see the results.
Mix white vinegar and baking soda and apply it under the arms 2 times a day. These are natural cleaners that will help you remove stains on your underarms.