A 30-year-old female complains of palpitations, fatigue, and insomnia. On physical exam, her extremities are warm and she is tachycardic. There is diffuse thyroid gland enlargement and proptosis. There is a thickening of the skin in the pretibial area. Which of the following lab values would you expect in this patient?

(b) Source: (Braunwald, 15/e, pp 2069-2074.) This patient has clinical symptoms of thyrotoxicosis. Most patients with thyrotoxicosis have increases in total and free concentrations of T3 and T4. (Some may have isolated T3 or T4 increases.) Most thyrotoxicosis results in suppression of pituitary TSH secretion, so low TSH levels can also confirm the diagnosis.