Hyperparathyroidism

Download the Hyperparathyroidism information sheet.

Hyperparathyroidism is a condition where the parathyroid glands make too much parathyroid hormone (PTH). PTH is an important hormone that helps control the balance of calcium and phosphate in your blood. There are four parathyroid glands located in the bottom of the neck, just behind the thyroid gland. Very rarely, people can have a parathyroid gland in other locations, for example in the upper chest (this is called an ‘ectopic’ parathyroid gland).

There are three types of hyperparathyroidism:

1. Primary hyperparathyroidism: This happens when one (or less commonly, several) parathyroid glands enlarge and make extra PTH, eventually leading to high blood calcium levels. Primary hyperparathyroidism is the most common type of hyperparathyroidism, thought to affect up to 1% of the population. It can be classified into two forms:

• Classical: Blood calcium is high in combination with a high (or sometimes normal) PTH level. This form is more likely to cause complications.
• Normocalcaemic: Blood calcium is normal but the PTH is high, without evidence of secondary causes (see secondary hyperparathyroidism). Some patients may later develop the classical form.

2. Secondary hyperparathyroidism: This is due to another condition causing low calcium levels, such as having too little vitamin D or kidney disease. The parathyroid glands make more PTH to keep the blood calcium level within a safe range.

3. Tertiary hyperparathyroidism: After a long period of time with secondary hyperparathyroidism, the parathyroid glands can remain overactive even when the underlying problem is treated. The blood calcium level becomes high.

In up to 90% of cases, primary hyperparathyroidism is due to non-cancerous growth of one of the four parathyroid glands, called an adenoma. It is not well understood why this occurs. Less commonly, it may be due to multiple glands getting bigger. This may be associated with a genetic condition or the medication lithium. Very rarely (<1% of cases), primary hyperparathyroidism can be due to cancer affecting a parathyroid gland.

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The symptoms of primary hyperparathyroidism depend on how severe it is and the length of time it has been present. Many people with mild disease will have no symptoms. Often symptoms can start slowly and worsen gradually over time as the blood calcium level rises. Many symptoms of hyperparathyroidism are not specific to this condition, and it is therefore hard to diagnose the condition early. Some symptoms are also common in people who do not have hyperparathyroidism. Working out the cause of your symptoms through blood tests is very important. Symptoms can include:

• Excessive thirst or urination
• Stomach pain and constipation
• Fatigue
• Low mood, anxiety or forgetfulness
• Bone and joint pain
• Nausea, vomiting or loss of appetite
• Weak bones that break easily (osteoporosis)
• Kidney stones

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1. Medical history

Your doctor may ask you questions about: Your personal health history, as well as your family’s health history. This will include questions about symptoms of parathyroid disease, osteoporosis, kidney disease or other endocrine disorders, any previous radiation therapy or neck surgery, your pregnancy history, current and previous medications, any other medical conditions or concerns, and your diet.

2. Physical examination

The physical examination may include feeling the front of your neck to check for parathyroid swelling.

3. Blood tests

If you have symptoms or signs of hyperparathyroidism, the next test your doctor will do is a blood test to measure the level of PTH, calcium, magnesium, phosphate, vitamin D, liver and kidney function. This involves taking a small amount of blood and sending it to the lab for tests.

4. Urine calcium test

If the calcium and PTH levels are higher than normal, your doctor will ask you to do a urine test to measure the amount of calcium in the urine. This involves collecting your urine over a 24-hour period and sending it to the lab for testing. You will be provided with the appropriate collection bottle. While this test is not as easy to do as a blood test, it is important to confirm the diagnosis of primary hyperparathyroidism. Primary hyperparathyroidism usually causes high levels of calcium in the urine. Low levels of calcium in the urine suggest a different diagnosis, for example a genetic condition called familial hypocalciuric hypercalcaemia, that does not require treatment.

What are the complications of primary hyperparathyroidism?

If primary hyperparathyroidism is not treated, it can lead to low quality of life due to symptoms (see symptoms section) as well as problems with the bones and the kidneys.

Your doctor may order a bone density test to see if you have developed osteoporosis. The best way to test bone mineral density (BMD) is using a DXA scan (Dual Energy X-ray Absorptiometry scan). This is a quick (10-20 minutes) and painless imaging procedure with very little radiation exposure. It involves lying fully clothed on a platform while a scanner passes over you to take pictures of your hip, spine and, sometimes, forearm.

Results are generally reported as a T score (see Osteoporosis fact sheet for more information on this).

• T-scores above -1.0 indicate normal bone density.

• T scores between -1.0 and -2.5 indicate osteopenia (slightly reduced bone density and possibly increased risk of fractures especially if T score is closer to -2.5).

• T scores below -2.5 indicate osteoporosis (low bone density and increased risk of bone fractures).

An x-ray of the spine may also be performed to look for fractures of the vertebrae. Spine fractures are common in primary hyperparathyroidism and may occur even without you noticing any symptoms.

Your doctor may also order an ultrasound of the kidneys to look for kidney stones or deposits of calcium in the kidneys (nephrocalcinosis). These can also occur without producing symptoms and over time can cause impaired kidney function.

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Observation: If your primary hyperparathyroidism is mild and not causing any complications, you may be recommended to undergo observation. This involves a blood test every 3-6 months to monitor the calcium and PTH levels. Your doctor will also keep an eye on your bone density over time, typically with a BMD (DXA) scan every 2 years, and kidney function, usually with a blood test at least yearly and a kidney ultrasound every 5 years. Around 25% of people under observation will develop a reason to require treatment during their lifetime.

Surgery: If your primary hyperparathyroidism is causing a very high blood calcium level or affecting your bones or kidneys, you may be referred to a surgeon for surgery to remove the overactive parathyroid gland(s). Before having surgery, scans are needed to identify which parathyroid gland(s) is overactive. Scans are only required if you are going to have surgery. There are several scans available and the scan recommended for you will depend on what is available in area you live and what your surgeon is familiar with. Most people with primary hyperparathyroidism will have an ultrasound of the neck, in addition to another test such as a Sestamibi scan or 4-dimensional CT scan. Your surgeon will discuss different types of surgery depending on the imaging results. A minimally invasive parathyroidectomy is often performed if the imaging clearly shows one overactive gland(s). A bilateral neck exploration may be required if the imaging does not clearly identify an overactive gland(s). Surgery that removes the overactive parathyroid gland(s) will cure the condition. If you have osteoporosis, this will usually improve slowly after surgery, although some people may require ongoing medication to strengthen their bones.

Medication: If you cannot or choose not to have surgery, there are some medications available to manage primary hyperparathyroidism and its complications. Cinacalcet is a calcimimetic, a drug that mimics calcium and tricks the parathyroid gland into releasing less PTH and lowering the blood calcium level. Osteoporosis treatment (for example, zoledronic acid, alendronate, risedronate or denosumab), can be used to manage high blood calcium levels and/or osteoporosis. These medications will not cure hyperparathyroidism as they do not reduce the release of PTH by the parathyroid glands.

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See your doctor if you have a family history of thyroid or Graves’ disease and develop symptoms.
See your doctor if you have any other side effects after starting your medication, such as a rash, hives, itchiness, painful joints, or nausea.
If you are taking anti-thyroid medication, see your doctor if symptoms change or get worse. Symptoms can change if your thyroid hormones get too low, which sometimes happens when the dose of medication needs adjustment. Symptoms caused by low thyroid hormones include tiredness or lethargy, unexpected weight gain, sensitivity to the cold and constipation. It is important to let your doctor know if you have taken more or fewer doses than prescribed so your dose can be adjusted correctly.

See your doctor immediately if you develop any fever, sore throat, skin rash, mouth ulcers, or abdominal pain after starting anti-thyroid medication. These side effects are very rare but need to be reported to your doctor who will do blood tests assessing full blood count and/or liver function.

Seeing your doctor or having a medical problem can be stressful. It often takes time for information to sink in, and it is very common to feel overwhelmed by what is happening. Sometimes it helps to write down questions before you go. Some questions that might be useful for you are:

• What is causing my hyperparathyroidism?
• Do I need further investigations?
• Do I need surgery?
• What do I do if I would like to get pregnant?
• Should my family members get tested?
• When do I need another appointment?

Where to go for information and support?

For information

Visit your doctor (GP)

Find an Endocrinologist: http://www.hormonesaustralia.org.au/find-an-endocrinologist/

For more information on parathyroid disorders during pregnancy and breastfeeding, visit “A patient parathyroid disorders guide during preconception, pregnancy and lactation“.

Healthy Bones Australia for more information on osteoporosis: Osteoporosis Prevention – Healthy Bones for Life without Fracture (healthybonesaustralia.org.au)

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Adenoma – A non-cancerous tumour in glands.

Autoimmune disorder – A condition where the body’s immune system attacks healthy cells.

Carcinoma – a type of cancerous tumour.

Tumour – An abnormal swelling or growth in the body. Can be benign (non-cancerous) or malignant (cancerous)

References

1. Milat F, Ramchand SK, Herath M, et al. Primary hyperparathyroidism in adults-(Part I) assessment and medical management: Position statement of the endocrine society of Australia, the Australian & New Zealand endocrine surgeons, and the Australian & New Zealand bone and mineral society. Clin Endocrinol (Oxf). 2024;100(1):3-18

2. Miller JA, Gundara J, Harper S, et al. Primary hyperparathyroidism in adults-(Part II) surgical management and postoperative follow-up: Position statement of the Endocrine Society of Australia, The Australian & New Zealand Endocrine Surgeons, and The Australian & New Zealand Bone and Mineral Society. Clin Endocrinol (Oxf). 2024;101(5):516-530. doi:10.1111/cen.14650

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Created by Dr Elizabeth Wootton (Endocrinologist, Royal Brisbane and Women’s Hospital)

Reviewed by Dr Karen Van (Endocrinologist, Hudson Institute of Medical Research), Dr Syndia Lazarus (Endocrinologist, Royal Brisbane and Women’s Hospital), Associate Professor Fran Milat (Endocrinologist, Hudson Institute of Medical Research and Monash Health) and Professor Mathis Grossmann (Endocrinologist, University of Melbourne at Austin Health)

Last reviewed 10 June 2026