Thyrotoxicosis is a condition that occurs when the thyroid gland emits excessive amounts of thyroid hormone, leading to elevated levels in the bloodstream. The syndrome is often related to hyperthyroidism, where the thyroid gland is overproducing hormones. It can also be caused by certain diseases or conditions that stimulate the thyroid to release extra stored hormones. The two hormones involved are free thyroxine and triiodothyronine.
One of the most common diseases that causes hyperthyroidism leading to thyrotoxicosis is Graves’ disease. This is an autoimmune disorder that causes the thyroid to generate excessive amounts of hormones. It is characterized by enlargement of the thyroid, also referred to as goiter.
Another issue that can frequently cause thyrotoxicosis is thyroiditis, or inflammation of the thyroid. There are various causes of this, including infection and autoimmune diseases. Sometimes women experience postpartum thyroiditis, which leads to hyperthyroidism during the first year after giving birth, though it is usually only for a limited time.
Various other issues can also be the source of thyrotoxicosis. Benign tumors, or thyroid adenomas, and multinodular goiters can become toxic and cause excess hormones to be created. Drugs and radiation treatments can also be contributing factors.
Symptoms of thyrotoxicosis typically include sweating, tremors, and an increased heart rate. Patients may also experience anxiety and oversensitivity to heat. Some sufferers may feel hungrier than usual, but will also lose weight. In the case of Graves’ disease, additional symptoms can include goiter and bulging of the eyes.
The first step to diagnosis is usually a physical examination. If the patient’s symptoms and physical state indicate thyrotoxicosis, the doctor will likely order a blood test. Low levels of thyroid-stimulating hormone and high levels of thyroxine or triiodothyronine confirm the diagnosis.
There are several treatment options available. Medications that inhibit the thyroid’s hormone production, called thyrostatics, can be used. Beta blockers may also be used, though they only treat the symptoms of thyrotoxicosis, not the cause. Sometimes surgery is recommended to remove some or all of the thyroid. Radioactive iodine can also be used to kill the overproducing cells in the thyroid.
If left untreated, thyrotoxicosis can lead to thyroid storm, or thyrotoxic crisis. This is a very dangerous condition that occurs when hormone levels in the blood reach extremely high levels. Patients experience high blood pressure, accelerated heartbeat, and a high fever. Thyroid storm needs to be treated immediately, as it can lead to death.