Updated on November 6, 2024 Overview of Hyperthyroidism Hyperthyroidism is an elevation of thyroid hormone (T3 and T4). Classification ClassificationDescriptionExamplesPrimary hyperthyroidismElevated thyroid hormone due to increased autonomous production by the thyroid gland. Has a low TSH, high T3 and T4Grave’s disease, Toxic nodular goiter (single toxic adenoma, toxic multinodular goiter), Thyroiditis (subacute, lymphocytic, post-partum), Struma...