Can Thyroid Problems Cause High Potassium?

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The thyroid gland plays an important role in your body’s metabolism. This small gland, located in the neck and only 2 inches wide, regulates the metabolism by secreting hormones that stimulate the body tissues. It also maintains the balance of calcium in the body and can affect potassium.


Potassium is an essential mineral and an electrolyte. Electrolytes are substances that can break down into charged particles known as ions, making them capable of conducting electricity. Potassium and sodium – another mineral and electrolyte – are critical to the transmission of nerve impulses across cell membranes. If these two minerals are out of balance, it can cause disruptions in nerve function, muscle contractions and heart function.

High and Low Potassium

Hyperkalemia is an abnormally high potassium level. It occurs when the kidneys cannot eliminate potassium fast enough to keep up with potassium intake. Symptoms include tingling of the hands and feet, muscular weakness and temporary paralysis. The most serious complication of hyperkalemia is an abnormal heart rhythm, which can lead to cardiac arrest and death. Hypokalemia is the opposite condition – abnormally low potassium. Although it most commonly occurs from prolonged vomiting, medication effects or kidney disease, hypokalemia is also seen in people with thyroid problems.


People with high levels of thyroid hormone or hyperthyroidism can develop a condition called thyrotoxic periodic paralysis. This problem develops after symptoms of hyperthyroidism occur. It involves attacks of muscle weakness or paralysis alternating with periods of normal muscle functions. During the attacks, the level of potassium in the blood is low; otherwise potassium is within normal limits. If the attacks continue over a period of time, the muscles become weak. Treating the hyperthyroidism can prevent attacks and may even reverse the muscle weakness.


In an early study of hyperthyroid patients reported in the March 1981issue of “Clinical Science,” potassium levels were measured in the patients during their treatments for hypothyroidism. As the thyroid hormone levels returned to normal, so did the potassium levels. However, according to a review published in the May 2011 issue of the “Journal of Hospital Medicine,” although low potassium and low thyroid levels are seen together, hypothyroidism does not actually cause the low potassium.

Considerations and Warnings

High potassium levels are not related to thyroid problems. Low potassium levels may be seen with low levels of thyroid hormones, but the thyroid does not cause them. Neither condition should be self-managed. If you have questions or concerns, consult a health care professional.