The uses of Synthroid - Levothyroxine include: Synthroid« (levothyroxine sodium tablets, USP) is a synthetic thyroid hormone intended to replace a hormone that is normally produced by your thyroid gland. Generally, thyroid replacement therapy is to be taken for life.
SYNTHROID should not be used for weight loss. Talk to your doctor about any medication and food allergies, all medications you are taking, pregnancy plans, and all medical conditions you may have, especially heart disease, clotting disorders, and adrenal or pituitary gland problems.
Tell your doctor if you experience: rapid or irregular heartbeat, chest pain, shortness of breath, leg cramps, headache, nervousness, irritability, sleeplessness, tremors, change in appetite, weight gain or loss, vomiting, diarrhea, excessive sweating, heat intolerance, fever, changes in menstrual periods, hives or skin rash, or any other unusual medical event.