Thyroid Disease: Pathophysiology, Diagnosis and ManagementAbout This Hardback The medical condition that affects the function of the thyroid gland is known as thyroid disease. Generally, there are five types of thyroid diseases, namely, hypothyroidism, hyperthyroidism, structural abnormalities, tumors and subclinical hypothyroidism. Each of them has their own symptoms. Symptoms of hyperthyroidism are tiredness, weight gain, muscle cramps, slow heart rate, constipation, etc. Symptoms of hyperthyroidism