Over activity of thyroid gland in human body is referred to as hyperthyroidism. As a result of this, the production of thyroxin hormone is paced up. This in turn leads to enhanced rate of metabolic activity. That is why people affected with this health issue become under-weight. It is due to increased combustion of blood glucose or sugar.
People diagnosed with hyperthyroidism may complain of physical weakness, tiredness, exhaustion, excessive perspiration and irritability in behaviour. There is swelling at the base of neck. Also the patient experiences irregular heartbeats. Such a person may become overly sensitive to heat. There is disturbance in sleep as well. Women suffering from this disorder may have disturbed or irregular menstrual cycles.