1 An adenoma is a part of the gland that has walled itself off from the rest of the gland, forming noncancerous (benign) lumps that may cause an enlargement of the thyroid. Not all adenomas produce excess T-4, and doctors aren't sure what causes some to begin producing too much hormone.  Thyroiditis.
Scratching Itchy Skin Causes Brain To Release Hormone Serotonin, Intensifies Itchy Sensation. While a good scratch may temporarily relieve you of your itch, it actually stimulates serotonin in the brain that intensifies the itchy feeling.
Youâre enjoying a beautiful day outside, when suddenly, a red, itchy welt raises up on your skin. Without thinking â or even knowing why mosquito bites itch â you instinctively start to scratch. Your skin reddens, the bite gets itchier and you start to notice two more red welts appearing from new bites.