The thyroid gland is part of the endocrine system and located just below the larynx. Its primary functions include regulating metabolism and the production of hormones throughout the body. To handle these duties, the thyroid produces two hormones of its own, triiodothyronine (T3) and thyroxine (T4). When the thyroid overproduces these two hormones, it causes an overstimulation of many other systems in the body causing a range of side effects that includes excessive sweating.
The overproduction of thyroid hormone is called hyperthyroidism. The most common cause of hyperthyroidism is an immune condition called Graves Disease, where the body attacks the cells of the thyroid in way that stimulates the overproduction of both T3 and T4. The overproduction of these hormones causes several other systems in the body, including the digestive, reproductive, dermal, and metabolic, to become overactive as well.
The over stimulation of these body systems results in a motley variety of symptoms. Common side effects of hyperthyroidism include frequent bowel movements, diarrhoea, insomnia, lightened or eliminated menstrual periods, dry skin, and a manic mental state characterised by mercurial moods, racing thoughts and irritability.
The body's metabolism is one of the major systems that is affected by an overproduction of thyroid hormone. The metabolism can be thought of the furnace of the body, as it is responsible for burning and storing energy. When metabolic function is heightened, there are a set of side effects which manifest, including significantly elevated resting heart rate, constant flushing of the skin, effortless weight loss, intolerance to heat and excessive sweating.
The excessive sweating caused by thyroid problems can be uncomfortable both physically and emotionally. However, this side effect will improve along with all the others once treatment, typically in the form of daily hormone suppressant tablets, is started. From the first dose, it takes between six and eight weeks to notice a decrease in hormone production and therefore a decrease in excessive sweating.
If oral medication is not solving the issue of the overactive thyroid, all or part of the gland can be removed either surgically or through radiation treatment to reduce the production of hormones. These treatments are meant as last resorts to handle the issue, and may result in the individual losing the ability to produce enough thyroid hormone. This condition is called hypothyroidism, and it has symptoms that are exact opposites to the symptoms of hyperthyroidism. After treatment, it is probable that an individual who once had issues with excessive sweating will find themselves intolerant to colder temperatures.