Image of glands responsible for primary hyperparathyroidism.
Patient Resources

Primary Hyperparathyroidism

January 24, 2022

Primary hyperparathyroidism (PHPT) is a condition in which one (or more) of your parathyroid glands produces too much parathyroid hormone and releases it in the bloodstream, often leading to high calcium levels.  

PHPT is one of the most common hormonal disorders. In the United States, about 100,000 people develop PHPT each year. The prevalence is about one to seven cases per 1,000 adults. It is more common in the African-American population. Women are more likely than men to develop PHPT, and the risk increases with age.   

Endocrine Connection 

The parathyroid glands are four pea-sized glands in the neck that produce parathyroid hormone (PTH). PTH keeps calcium at a normal level in the blood, so it can do its job in the body. For instance, calcium helps nerves work properly and maintains a healthy blood pressure. When blood calcium gets low, PTH brings it back to normal by moving calcium from the bones, kidneys, and intestines into the blood. 

Too much PTH causes more calcium to be released from the bones and raises levels of calcium in the blood and urine above normal. Over time, this can result in weak bones that break easily, kidney stones (small clumps of calcium), and a decline in kidney function. 

The most common cause of primary hyperparathyroidism is a single noncancerous (benign) growth called an adenoma on one of the parathyroid glands. An adenoma causes the gland to become overactive and make more PTH. Less often, all four parathyroid glands become enlarged and produce too much PTH. Sometimes PHPT results from radiation to the neck area or the use of certain medications (thiazide diuretics or lithium). In a small number of cases, people inherit a gene that leads to PHPT. Rarely, parathyroid cancer causes PHPT.

Health care providers most often diagnose PHPT with blood tests that detect high calcium and PTH levels. When PHPT is found, further tests may be done to check for complications, including: 

  • Blood tests to check how well the kidneys are working 
  • A measure of calcium levels in urine which can guide in the cause of the elevated blood calcium  
  • Imaging tests such as ultrasound or CT scan to look for kidney stones 
  • A blood test for vitamin D to see if a low vitamin D level is affecting PHPT 
  • A bone mineral density test called a DEXA scan—a type of X-ray that checks bone strength. In some cases, patients also receive testing for genetic forms of the condition. 

It has been hypothesized that taking low (not enough) calcium for a long time may increase the risk of developing PHPT by causing chronic stimulation of the parathyroid gland. Depending your gender and age, there are different recommendations about how much calcium you should be getting daily. For most adults, at least 1,000 mg of calcium daily is recommended.  

PHPT can also cause complications, such as: 

  • Gastrointestinal effects: high levels of calcium in the blood can cause heart burn, constipation, abdominal pain and gall stones formation. It can also, rarely, cause pancreatitis, which is an inflammation of the pancreas.  
  • A condition called “parathyroid crisis” which occurs when the blood calcium levels are very high and causes  neurological symptoms like confusion, extreme lethargy and even coma in some cases. 
  • High levels of calcium can increase blood pressure and cause heart rhythm abnormalities. This occurs due to deposition of calcium within the blood vessels and heart muscle.  
  • A condition called “Pseudo gout” – a type of gout where calcium gets deposited in the joints.  
  • Abnormalities in other chemicals in the body – it can decrease blood phosphorus levels and increase blood magnesium levels.  

Signs and symptoms of PHPT include:



  • Fatigue (feeling very tired) 
  • Depression 
  • Anxiety 
  • General aches and pains 
  • Flank pain or blood in the urine from kidney stones
  • Nausea and vomiting 
  • Bone pain 
  • Increased thirst and urination 
  • Constipation 
  • Forgetfulness 
  • Confusion 


Some people have no symptoms (what you feel) at all. While most people with benign PHPT do not have severe symptoms, those with parathyroid cancer almost always do. 

Women are more likely than men to develop primary hyperparathyroidism, and the risk increases with age. Sometimes, radiation to the neck region (for example, radiation given as part of treatment for cancers) can increase the risk of developing this condition as well. Taking low calcium for a long time may also increase the risk of developing PHPT

The doctor chooses a treatment based on a patient’s age, test results, and which signs or symptoms are present. 


Surgical removal of adenomas or enlarged parathyroid glands is recommended for all patients under the age of 50, whether or not they have symptoms. This is because young people tend to develop more complications over time if they are untreated. 

Surgery also is suggested for people with: 

  • Osteoporosis or kidney stones 
  • High levels of blood calcium (above a certain level) 
  • Impaired kidney function
  • High levels of urinary calcium  

To locate the exact site of excess PTH production and to plan surgery, the doctor may order one or more of the following imaging tests: 

Neck Ultrasound: This is an imaging study where an ultrasound probe is used to get a better look at the parathyroid glands. 

CT Scan of the Neck: This test uses a computer linked to an x-ray machine to make a series of detailed pictures of areas inside the body. 

Sestamibi Scan: For this test, an injection of a small amount of radioactive dye in given through the vein. The overactive parathyroid gland or glands then absorb the dye. The surgeon can see where the dye has been absorbed by using a special camera.  


For some patients without signs or symptoms, doctors recommend regular checkups instead of surgery. Tests should include blood calcium levels, blood tests to check kidney function, and checks of bone density. A doctor may also prescribe medicines, including: 

  • Calcimimetics: These drugs tell the body to make less PTH, helping to lower blood calcium levels. 
    Bisphosphonates: These drugs help keep bones strong by keeping calcium in the bones. 

Lifestyle Changes 

There are many lifestyle changes that can help with PHPT including:

  • Drinking plenty of water and avoid dehydration. This will help prevent formation of kidney stones. 
  • Taking a vitamin D supplement if your vitamin D levels are low. 
  • Getting regular physical exercise to help keep your bones strong. 
  • Avoiding certain medications that can increase blood calcium levels. Talk to your doctor before starting any new medications to make sure that they are safe for you. 

It is important to note that you don’t need to change your diet or limit the amount of calcium you get from food and beverages.  

Surgery is highly successful for people with PHPT and provides a cure. In those for whom surgery is not the best option, regular checkups and medicines can help control symptoms and reduce complications. Doctors continue to research the best ways to diagnose and treat PHPT.

  • Do I have PHPT? 
  • If so, what caused my PHPT? 
  • Will I need surgery? 
  • What are my other treatment options? 
  • What are the benefits and risks of each treatment? 
  • Should I see an endocrinologist? 

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