Parathyroid glands

Your parathyroid glands are 4 small glands located behind the thyroid gland in your neck. They are part of your endocrine (hormonal) system.

Despite their small size, they play an important role in keeping your body healthy. These glands produce a hormone that controls your blood calcium levels. This is important for healthy bones, muscles and nerves.

Your parathyroid glands make parathyroid hormone (PTH). Parathyroid hormone help regulate calcium levels in your blood and bones. Calcium is an important mineral for the healthy functioning of your:

• nerves
• muscles
• heart
• kidneys

PTH works by raising calcium levels in your blood when they drop too low. It does this by:

• adjusting the amount of calcium released by your bones into your blood
• managing the amount of calcium that is removed by your kidneys via your urine (wee)
• increasing calcium absorption from your diet through the intestines

Without regulation by your parathyroid glands, calcium levels could become too high or too low. This may lead to issues, such as:

• weak bones
• muscle problems
• nerve dysfunction

A range of medical conditions can affect your parathyroid glands.

• Parathyroid tumours may result in your parathyroid glands making too much parathyroid hormone. Most parathyroid tumours are adenomas (non-cancerous).
• In some autoimmune conditions, the immune system mistakenly attacks the parathyroid glands. This may result in your parathyroid glands making too little parathyroid hormone.
• Some rare genetic disorders lead to improper gland development or function. This may result in your parathyroid glands making too much or too little parathyroid hormone.
• Chronic kidney disease may result in your parathyroid glands making too much parathyroid hormone.
• Vitamin D is important for calcium absorption. Vitamin D deficiency can disrupt the calcium balance in your blood, leading to health issues.
• Surgical damage may result in your parathyroid glands making too little parathyroid hormone.

If your parathyroid glands produce too much or too little parathyroid hormone, it can lead to:

• hyperparathyroidism
• hypoparathyroidism

These conditions are different from hyperthyroidism and hypothyroidism.

Hyperparathyroidism

Hyperparathyroidism happens when your parathyroid glands produce too much PTH. This leads to high calcium levels in your blood (hypercalcaemia) and can affect several body systems.

Symptoms may include:

• muscle weakness, fatigue and loss of appetite
• bone pain and fractures
• kidney stones and frequent urination (wee)
• emotional changes, memory loss and irritability

Hyperparathyroidism may be caused by:

• a benign tumour (adenoma) in one of the parathyroid glands
• low calcium levels due to chronic kidney disease or vitamin D deficiency
• chronic kidney disease, causing the parathyroid glands to continue to produce PTH even with normal calcium levels

Hyperparathyroidism may be diagnosed through blood tests, a bone density scan and urine tests.

Hyperparathyroidism may be treated by removing the overactive parathyroid glands through surgery. Your doctor may also recommend lifestyle changes and medicines.

Severe hyperparathyroidism may lead to pancreatitis, heart issues and osteoporosis.

Hypoparathyroidism

Hypoparathyroidism is when your parathyroid glands don't make enough parathyroid hormone. This leads to low calcium levels in your blood (hypocalcaemia).

What are the symptoms of hypoparathyroidism?

Symptoms may include:

• tingling in your lips, hands and feet
• muscle cramps and painful spasms
• difficulty breathing or swallowing (in severe cases)

Hypoparathyroidism is rare. It usually happens if your parathyroid glands are damaged during neck surgery, for example, surgery for thyroid problems or hyperparathyroidism.

It may also be caused by autoimmune conditions, severe magnesium deficiency or rare genetic conditions.

Hypoparathyroidism may be diagnosed with a blood test.

Treatment may include receiving medicine (calcium) through a vein (IV or 'drip'). Your heart function will be monitored with an electrocardiogram (ECG) during this treatment.

Your doctor may also recommend calcium and vitamin D supplements and a high-calcium diet. Foods high in oxalic acid, such as spinach, should be avoided, as they block calcium absorption.

Complications may include changes in bone density and mental health issues.

• Australian Thyroid Foundation (Opens in new tab) provides information about parathyroid glands.
• Hormones Australia (Opens in new tab) offers support and resources on hormone-related conditions and endocrine glands, including the parathyroid gland.
• Hormones Australia (Opens in new tab) can also help you find an endocrinologist.

You can also call the healthdirect helpline on 1800 022 222 (known as NURSE-ON-CALL in Victoria). A registered nurse is available to speak with you 24 hours a day, 7 days a week.