Kidney & Electrolytes
Parathyroid Hormone (PTH)
Kidney & Electrolytes
Regulates calcium and phosphorus. Elevated in vitamin D deficiency and bone disease.
VAT-exempt medical service
PTH is produced by the four parathyroid glands located behind the thyroid. When blood calcium drops, the parathyroids release PTH to mobilise calcium from bones, increase calcium reabsorption in the kidneys, and stimulate vitamin D activation for better intestinal absorption. Conversely, when calcium is high, PTH secretion is suppressed. Measuring PTH alongside calcium and phosphate helps diagnose parathyroid disorders, vitamin D deficiency, and chronic kidney disease.
A PTH test is recommended when calcium levels are abnormal, when parathyroid dysfunction is suspected, or when evaluating bone health, vitamin D status, or kidney disease. It is essential for distinguishing between the many causes of high or low calcium and for guiding treatment of conditions like osteoporosis.
What a high value can mean
Elevated PTH (hyperparathyroidism) can be primary -- caused by a parathyroid adenoma or hyperplasia -- or secondary, in response to low calcium, vitamin D deficiency, or chronic kidney disease. High PTH increases bone resorption, raises blood calcium, and can lead to kidney stones and weakened bones over time.
What a low value can mean
Low PTH (hypoparathyroidism) may result from surgical damage to the parathyroid glands, autoimmune destruction, or magnesium deficiency. It leads to low blood calcium and high phosphate, which can cause muscle cramps, numbness, and tingling.
No special preparation is required. Bring a valid ID. Morning sampling may be preferred as PTH follows a circadian rhythm.
Order your test
Choose your test and pay online. Your lab referral is created straight away.
Give your sample
Visit any of our partner sampling locations. No appointment needed at most of them.
The lab analyses it
Your sample is analysed at an accredited Swedish laboratory.
Get your results
Your values appear in your account with reference ranges and an explanation of each marker.
PTH raises blood calcium when levels are low by releasing calcium from bones, reducing calcium loss through the kidneys, and increasing calcium absorption from food via vitamin D. When calcium is adequate, PTH secretion decreases.
Yes. In chronic kidney disease, the kidneys cannot activate vitamin D or excrete phosphate efficiently. This leads to low calcium and chronically elevated PTH -- a condition called secondary hyperparathyroidism.
PTH is a hormone that regulates both calcium and phosphate. Phosphate is a mineral. PTH raises calcium and lowers phosphate. Testing both helps your doctor understand the full metabolic picture.
Yes. PTH is most informative when interpreted alongside calcium, phosphate, vitamin D, and kidney function tests. This combination allows accurate diagnosis of parathyroid and metabolic bone disorders.