Hello, Thank you for your question. Hypothyroidism i a condition that makes you feel tired. There is a gland in your neck called the thyroid gland. It make thyroid hormone. This hormone controls how the body uses and stores energy. Hypothyroidism is the medical term for when a person does not make enough thyroid hormone. Some people with hypothyroidism have no symptom. But most people feel tired. That can make the condition hard diagnosis, because a lot of conditions can make you tired. Other symptoms of hypothyroidism include: lack of energy, getting cold easily, developing coarse or thin hair, getting constipated. If it is not treated, hypothyroidism can also weaken and slow your heart. Untreated hypothyroidism can also increase your blood pressure and raise your cholesterol. Treatment for hypothyroid involves taking thyroid hormone pills every day. After you take the pills for about 6 weeks, your doctor will test you blood to make sure the levels are where they should be. Your doctor might adjust your dose depending on the result. Most people with hypothyroidism need to be on thyroid pills for the rest of their life. Thyroid hormone pills come in different brand name and generic forms. All the pills work equally well. But you should not switch from one generic or brand name to another. Switching between pills can cause your levels to go up and down. Never change your dose of thyroid hormone on your own. Taking too much thyroid hormone can cause heart rhythm problems and even damage your bone. Hope I have answered your query. Let me know if I can assist you further. Best regards, Dr. Heang Chan Raksmey, General and Family Physician.