The hormones made by the thyroid gland stimulate the basal metabolism of the body. In hyperthyroidism there is abnormally high production and secretion of T3 and T4 so the basal metabolic rate is increased. The signs of this condition may be tachycardia (abnormally high heart rate), weight loss, excessive heat sensation, excessive sweating, anxiety, etc. One of the typical signs of hyperthyroidism is exophthalmos (protrusion of the eyeballs). Generally the patient also presents goiter.