Hyperthyroidism or Hyperactive Thyroid: Symptoms, Causes and Treatments

Definition: the overactive thyroid, is a condition in which the thyroid gland produces too much of the hormone thyroxine .

Hyperthyroidism accelerates the metabolism of the body significantly, causing sudden weight loss, rapid and irregular heartbeat, sweating and nervousness or irritability.

There are several treatment options available to treat this condition. Doctors use anti-thyroid medications and radioactive iodine to decrease the production of this type of hormones.

Sometimes, the treatment of hyperthyroidism lies in surgery to remove all or part of the thyroid gland.

Although hyperthyroidism can be serious, most people respond successfully to treatment once it is diagnosed and treated early.


Hyperthyroidism can mimic other health problems, which can make it difficult to diagnose. It can also cause a wide variety of signs and symptoms:

  • Sudden weight loss
  • Rapid heartbeat (tachycardia), irregular heartbeat (arrhythmia) or heartbeat (palpitations).
  • Increased appetite
  • Nervousness, anxiety and irritability.
  • Tremor in hands and fingers.
  • Excessive sweating
  • Variations in menstrual hormones.
  • Increased sensitivity to heat.
  • Enlargement of the thyroid gland.
  • Fatigue.
  • Muscular weakness.
  • Difficulty to sleep.
  • Thinning of the skin
  • Fine and brittle hair.

Older adults are more likely to have signs or symptoms, such as: increased heart rate, heat intolerance and fatigue during ordinary activities.

Medications called beta-blockers are used to treat high blood pressure and other conditions, and these can conceal several of the symptoms of hyperthyroidism.


Some conditions such as: Graves’ disease, toxic adenoma, Plummer’s disease (toxic multinodular goiter) and thyroiditis can cause hyperthyroidism.

The thyroid gland, which has a butterfly shape and is located at the base of the neck, just below the “Adam’s apple”, despite being very small and weighing less than an ounce, the thyroid gland has a huge impact In the health.

All aspects of metabolism are regulated by thyroid hormones.

This gland produces two main hormones: thyroxine (T-4) and triiodothyronine (T-3), these hormones influence every cell in the body.

As for example: they maintain the speed in which the body handles fats and carbohydrates, they help to control the heart rate, the temperature of the body and to regulate the production of proteins.

Similarly, the thyroid also produces calcitonin, a hormone that regulates the amount of calcium in the blood.

Tests and diagnosis

Clinical history and physical examination . During the exam, the doctor may detect a slight tremor in the fingers when they are stretched, hyperactive reflexes, changes in the eyes, hot and moist skin.

Blood tests . The diagnosis can be confirmed by blood tests, which will measure thyroxine and TSH levels.

High levels of thyroxine and low amounts of TSH indicate that there is an overactive thyroid. The amount of TSH is important because it is the hormone that tells the thyroid gland when to produce more thyroxine.

These tests are especially necessary for older adults, who may not have the classic symptoms of hyperthyroidism.

If blood tests indicate hyperthyroidism, the doctor may recommend performing:

Radio iodine absorption test . For this test, you take a small, oral dose of radioactive iodine. After a few minutes, the iodine will accumulate in the thyroid, after 2, 6 or 24 hours, the amount of iodine that the thyroid gland has absorbed will be determined.

A high absorption of radioactive iodine indicates that the gland is producing excessive thyroxine. The most likely cause is hyperfunctioning disease or due to severe nodules.

Thyroid examination . During this test, a radioactive isotope will be injected into the vein on the inside of the elbow or into a vein in the hand.

Next, the patient lies on a table with his head stretched back, a special camera will capture an image of the thyroid gland on a screen.

The time needed for this procedure varies depending on how long it takes for the isotope to reach the gland.

During the performance of this test, there may be discomfort in the neck, apart from the fact that the person is exposed to low levels of radiation.

Treatment of Hyperthyroidism

The radioactive iodine . It is taken orally, and is absorbed by the thyroid gland, where it causes the gland to shrink and symptoms to decrease, usually within three to six months.

This treatment has been used for more than 60 years, and radioactive iodine has been shown to be generally safe.

Anti-thyroid drugs . They progressively reduce the symptoms of hyperthyroidism by preventing the thyroid gland from producing huge amounts of hormones, these include: propylthiouracil and methimazole (Tapazole).

Symptoms usually begin to improve from 6 to 12 weeks, but treatment with anti-thyroid medications usually continues for at least a year and often longer.

For some people, this clarifies the problem permanently, but other people have experienced a relapse.

Both drugs can cause severe liver damage and sometimes cause death. Because propylthiouracil causes severe liver damage, it should only be used when methimazole can not be tolerated.

A small number of people who are allergic to these drugs may develop skin rashes, hives, fever or joint pain. It can also make them more susceptible to infection.

Beta blockers . Commonly used to treat very high blood pressure. It does not lower thyroid levels, but it can reduce the heart rate quickly and helps prevent heart palpitations.

Some of the most common side effects are: fatigue, headache, upset stomach, constipation, diarrhea or dizziness.

Surgery (thyroidectomy) The doctor removes most of the thyroid gland. The risks of this surgery include damage to the vocal cords and parathyroid glands.

If the parathyroid glands are also removed, you will need medications to keep your blood calcium levels at normal levels.