text: Did he check the TSH (thyroid stimulating hormone), which is a pituitary hormone which stimulates the thyroid??  The usual cause of hyperthyroidism is a diffuse enlargement of the thyroid gland.  You have high thyroxin (T4) and low TSH (the high T4 causes feedback inhibition on the anterior pituitary gland, and lowers the TSH).  In fact, the TSH is often a more sensitive test for Graves disease than the T4. Sometimes your T4 will be in normal range, but if you got a low TSH, you probably got hyperthyroidism.  Also, your eyes may look a little bulging. Rapid pulse, heat intolerance, fine tremor, losing weight, sure---irregular periods, all can be signs of hyperthyroidism.  You expect the person to be a little manic and skinny, but there is an "apathetic hyperthyroidism", where they get kind of burned out on the high hormone, and start to put weight back on and look depressed.  Of course, if you got a very high TSH and a high T4, then it means you got a little tumour of your anterior pituitary gland causing the high thyroid, and sometimes other hormone imbalances as well.\n\nAn endocrinologist is the expert.  There are lots of subtleties to this I'm not totally aware of.  But i'm thinking you might still have hyperthyroidism and need treatment with PTL (propylthiouracil) at least, if not radioactive iodine ablation therapy or surgical subtotal thyroidectomy, which are the treatment options.  I would get a thyroid scan.  That tells you more.  Otherwise, see an endocrinologist.  Also, if you have been on any meds or drugs, this can effect your thyroid function.  Lithium, used to treat bipolar disorder, certainly messes with the thyroid.  I believe depression can affect it as well.  So can alcoholism.