Test library
Parathyroid Hormone Test
A Parathyroid Hormone test measures PTH, the hormone that regulates blood calcium. It is used to evaluate parathyroid function and is interpreted together with calcium and related tests.
Order Parathyroid Hormone (PTH) Test
Order online and visit a local collection site, or choose an at-home kit where available. No referral and no insurance required.
Order Parathyroid Hormone (PTH) Test- Typical turnaround
- 1-3 business days
- Starting price
- From $158
- Results
- Confidential, online
Quick answer
The Parathyroid Hormone test measures the level of PTH in the blood. PTH is released by the parathyroid glands and is the main regulator of calcium balance in the body. The test is usually interpreted alongside a calcium measurement, because together they help show whether the parathyroid glands are responding appropriately.
What this test measures
The parathyroid glands sit near the thyroid in the neck and release PTH in response to low blood calcium. PTH raises calcium by acting on bone, the kidneys, and the gut. Because calcium and PTH work in a tight feedback loop, measuring PTH alone can be misleading, so clinicians typically review it with calcium and sometimes vitamin D or phosphate.
Testing may be ordered when a routine blood test shows abnormal calcium, or when someone has symptoms that could relate to parathyroid function, such as bone discomfort, kidney stones, or fatigue. It can also be used to follow a known parathyroid condition or to investigate an unclear calcium problem.
Interpretation depends on context. A high PTH with a high calcium points in one direction, while a high PTH with a low calcium points in another. Results can be influenced by vitamin D status, kidney function, and medications, so a qualified healthcare provider evaluates the whole picture before drawing conclusions.
- Parathyroid hormone (PTH), also called parathormone
- Serum calcium, often ordered at the same draw
- Ionized calcium when requested
- Vitamin D (25-hydroxyvitamin D)
- Phosphate (phosphorus)
- Magnesium
- Albumin, used to adjust total calcium
- Serum creatinine to assess kidney function
Why people order this test
- Investigate an abnormal calcium result
- Evaluate suspected parathyroid overactivity or underactivity
- Support the workup of kidney stones or bone concerns
- Monitor a known parathyroid condition over time
- Check PTH after parathyroid surgery
- Clarify the cause of unexplained fatigue or bone discomfort
How to prepare
Fasting may be requested depending on which tests are bundled with the order, since calcium and some related markers are sometimes measured after fasting. A blood sample is collected from a vein. Follow the timing and preparation instructions provided by the laboratory.
Understanding your results
Results are usually available within one to three business days. The report shows the PTH level, which is interpreted together with calcium and any related tests. Values outside the reference range do not diagnose a condition by themselves, so a qualified healthcare provider evaluates them in context.
Parathyroid Hormone Test by state
Alabama
Parathyroid Hormone Test across Alabama.
Alaska
Parathyroid Hormone Test across Alaska.
Arizona
Parathyroid Hormone Test across Arizona.
Arkansas
Parathyroid Hormone Test across Arkansas.
California
Parathyroid Hormone Test across California.
Colorado
Parathyroid Hormone Test across Colorado.
Connecticut
Parathyroid Hormone Test across Connecticut.
Delaware
Parathyroid Hormone Test across Delaware.
Florida
Parathyroid Hormone Test across Florida.
Georgia
Parathyroid Hormone Test across Georgia.
Hawaii
Parathyroid Hormone Test across Hawaii.
Idaho
Parathyroid Hormone Test across Idaho.
Related tests
12 Panel Drug Test (Drugs of Abuse Testing), Hair
Compare 12 Panel Drug Test (Drugs of Abuse Testing), Hair options and order online.
12 Panel Drug Testing
Compare 12 Panel Drug Testing options and order online.
7 Panel Drug Test (Drugs of Abuse Testing), Hair
Compare 7 Panel Drug Test (Drugs of Abuse Testing), Hair options and order online.
9 Panel Drug Test
Compare 9 Panel Drug Test options and order online.
9 Panel Drug Test (Drugs of Abuse Testing), Hair
Compare 9 Panel Drug Test (Drugs of Abuse Testing), Hair options and order online.
Frequently Asked Questions
What does parathyroid hormone do?
PTH regulates calcium in the blood. It raises calcium by acting on bone, the kidneys, and the gut, helping keep levels within a narrow range.
Why is calcium tested with PTH?
The two are interpreted together. The relationship between PTH and calcium helps clinicians understand whether an abnormality involves the parathyroid glands or another cause.
Do I need to fast for this test?
Fasting may be requested depending on which tests are ordered with it. Follow the preparation instructions supplied with the order.
Can vitamin D affect the result?
Yes. Vitamin D status influences calcium and PTH, so it is often measured alongside them to give a fuller picture.
Where are the parathyroid glands?
They are four small glands located near the thyroid gland in the neck. Despite the similar name, they have a different function from the thyroid.
Ready to get tested?
Order online and visit a collection site near you, or choose a mail-in kit. No referral and no insurance required.
Reviewed by the LabOrdering Editorial Team
Every page on this site is reviewed for clarity, sourcing, and accuracy. We update our library as testing options, collection networks, and accreditation standards change.