Acanthosis nigricans describes a pattern of hyperpigmentation that results in dark and velvety patches of skin around the neck, armpits, groin, and other skin folds. This condition is almost always an indicator of some internal hormonal imbalance. There are five types of acanthosis nigricans. Read more to find out what they are and how they are treated.
Urticaria, also known as hives or welts, is common skin reaction to one of many triggers. It appears as raised, red, and intensely itchy wheals that usually recede within hours or days. Read more to learn about treatment options.