What is the Difference Between Thyrotoxicosis and Hyperthyroidism?

Thyrotoxicosis and hyperthyroidism are related but distinct conditions involving thyroid hormones. Here are the main differences between the two:

• Thyrotoxicosis refers to the clinical syndrome of excess circulating thyroid hormones, irrespective of the source. It is a hypermetabolic condition caused by an inappropriately high level of circulating thyroid hormones.
• Hyperthyroidism is characterized by increased thyroid hormone synthesis and secretion from the thyroid gland. It is a specific cause of thyrotoxicosis, where the excess thyroid hormones are produced by the thyroid gland itself. The most common cause of hyperthyroidism is Graves' disease, followed by toxic nodular goiter.

Both conditions can lead to similar symptoms, such as nervousness, anxiety, increased perspiration, heat intolerance, hyperactivity, palpitations, and weight loss despite increased appetite. However, the underlying causes and treatment approaches may differ. For example, thyrotoxicosis can be caused by factors such as thyroiditis, iodine-induced and drug-induced thyroid dysfunction, and factitious ingestion of excess thyroid hormones. Treatment for thyrotoxicosis depends on the underlying cause, and may include antithyroid medications, radioactive iodine ablation, or surgery.

Comparative Table: Thyrotoxicosis vs Hyperthyroidism

Thyrotoxicosis and hyperthyroidism are related but distinct medical conditions involving thyroid hormones. Here is a table highlighting the differences between the two:

While thyrotoxicosis is a condition where there are excess circulating thyroid hormones, hyperthyroidism specifically refers to the elevated thyroid gland function that leads to this excess. Both conditions share similar symptoms and methods of diagnosis, but their causes and underlying mechanisms differ.