Excessive underarm perspiration is fairly a general trouble with youthful adults these days. It could be a sign of a severe medical matter such as rheumatoid arthritis, an overactive thyroid gland etc. Perspiration, also recognized as sweating or diaphoresis, is the manufacture of fluids secreted by the sweat glands in the skin of mammals. Two types of sweat glands can be found in humans such as eccrine glands and apocrine glands. The eccrine sweat glands are distributed over much of the body.