Hyperthyroidism generally refers to hyperthyroidism, while hypothyroidism generally refers to hypothyroidism. Hyperthyroidism may have symptoms such as palpitations and weight loss; hypothyroidism may have symptoms such as bradycardia and constipation, and prompt medical attention is recommended. Hyperthyroidism is caused by excessive production of thyroid hormones. Clinical manifestations include palpitations, weight loss, diarrhea, agitation, irritability, fatigue, fear of heat, excessive sweating, and increased bowel movements. Hypothyroidism is a systemic disease caused by insufficient secretion of thyroid hormones, with clinical manifestations including fatigue, chills, unresponsiveness, constipation, bradycardia, and depressed mood. Patients with symptoms of hypothyroidism or hyperthyroidism are advised to go to the hospital and ask the doctor to make a clear diagnosis and then take active treatment.