If a person does not receive treatment, hyperthyroidism can have serious effects. One of these is a life threatening condition called thyroid storm.

During a thyroid storm, a person’s heart rate, body temperature, and blood pressure can rapidly increase. While a thyroid storm can be fatal without treatment, most people improve within 24 hours if they receive treatment.

If a person has hyperthyroidism, they can manage the condition with medication. Doctors may prescribe a quick-acting medication to relieve symptoms until a slower-acting treatment has time to produce the desired results.

Keep reading to learn more about the health effects of hyperthyroidism, thyroid storm, and how to manage the condition.

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Hyperthyroidism causes many body functions to speed up. Symptoms of the condition include:

  • rapid or irregular heartbeat
  • shaky hands and muscle weakness
  • weight loss despite an increased appetite
  • frequent bowel movements
  • nervousness, trouble sleeping, irritability, and tiredness
  • sweating or heat intolerance
  • a goiter, an enlargement of the thyroid gland at the base of the neck

The symptoms may differ in older adults, as they may experience a loss of appetite or withdraw from others.

Hyperthyroidism is manageable if a person seeks treatment and has regular check-ups with a doctor. However, if they do not receive treatment, they are at risk of the following complications:

  • an eye disease called Graves’ ophthalmopathy, where the eyeballs protrude forward from their sockets
  • menstrual cycle and fertility issues
  • muscle problems, thinning bones, and osteoporosis

One of the complications of untreated hyperthyroidism is an irregular heartbeat. This can lead to serious effects, including:

Additionally, without treatment, hyperthyroidism can become extreme hyperthyroidism, which doctors also refer to as a thyroid storm.

Thyroid storm is a potentially life threatening condition that may cause:

  • an irregular heartbeat
  • atrial fibrillation, a very rapid heartbeat that can lead to blood clots in the heart
  • vomiting and diarrhea
  • seizures, delirium, and coma

If a person has symptoms of a thyroid storm, they should seek medical attention right away. The condition is manageable if they receive prompt treatment.

However, without treatment, a thyroid storm can be life threatening, with a death rate of 8–25%. The cause of death may be due to:

  • heart failure
  • irregular heartbeat
  • multiple organ failure

Most individuals with thyroid storm improve within 24 hours after treatment. However, not every person recovers, and risk factors for a negative outlook include:

  • advanced age
  • the need for kidney dialysis or mechanical ventilation, a machine to enable breathing
  • neurological deficits

Treatment for hyperthyroidism varies and depends on the cause and severity of a person’s condition. Some treatment options include medication, radioiodine therapy, and surgery.


Doctors may prescribe beta-blockers or antithyroid drugs.


These widen blood vessels and block the action of substances on nerve cells. They can reduce symptoms until other thyroid medication starts working, but they do not stop the thyroid gland from making hormones.

One example of a beta-blocker is atenolol (Tenormin).

Antithyroid drugs

These cause the thyroid gland to produce less hormones. However, they do not provide a permanent cure. They also do not work fast — it typically takes several weeks or months before thyroid levels return to typical levels.

One example of an antithyroid drug is methimazole (Tapazole).

Radioiodine therapy

This is a common and very effective treatment. It slowly destroys cells in the thyroid gland that make hormones.

Most people who receive this treatment later develop hypothyroidism, a condition where a person has low levels of thyroid hormones. However, this is easily treatable with daily hormone medication.


Surgery involves the surgical removal of part or all of the thyroid gland. These procedures may return thyroid hormones to typical levels, but it carries a risk of sudden and severe worsening of symptoms.

Someone with symptoms of hyperthyroidism can consult a doctor.

However, it is important to recognize thyroid storm early, so if an individual has symptoms of this complication, they need to seek immediate medical attention.

Medications for hyperthyroid treatment can also have serious side effects. People who take one of them should call a doctor right away if they experience:

  • tiredness or weakness
  • loss of appetite
  • yellowing of the skin or whites of the eyes
  • a dull pain in the abdomen
  • rash, easy bruising, or itching
  • chills, fever, or constant sore throat

Without treatment, hyperthyroidism can have serious effects such as stroke and blood clots. It can also cause a thyroid storm, which is fatal in 8–25% of people.

Treatment depends on the underlying cause of hyperthyroidism, but options may include medications, radioiodine therapy, and surgery. If a person experiences any symptoms of a thyroid storm, they should seek urgent medical attention.