Toxic goiter, also known as Graves' disease, is a condition where the thyroid gland becomes enlarged and produces excessive amounts of thyroid hormones. This overproduction can lead to symptoms such as weight loss, increased heart rate, and anxiety. The condition is often caused by an autoimmune response, where the body's immune system mistakenly attacks the thyroid. Diagnosis typically involves blood tests to measure hormone levels and imaging studies to assess the size of the thyroid. Treatment options may include medications to regulate hormone production, radioactive iodine therapy, or surgery to remove part of the thyroid gland.