toxic nodular goiter, an enlarged thyroid gland characterized by numerous discrete nodules and hypersecretion of thyroid hormones. It occurs most frequently in elderly individuals. Typical signs of thyrotoxicosis such as nervousness, tremor, weakness, fatigue, weight loss, and irritability are usually present, but exophthalmia is rare. Anorexia is more common than hyperphagia, and cardiac arrhythmia or congestive heart failure may be a predominant manifestation. When clinical findings suggest thyrotoxicosis, a therapeutic trial of antithyroid drugs, such as propylthiouracil or methimazol, is indicated, but, after the diagnosis is established, radioactive iodine is considered the treatment of choice, and large doses are usually required.
