What is this test?
Parathyroid hormone is produced by the parathyroid glands and helps regulate calcium and phosphate in the blood and bones.
Why might it be ordered?
- When calcium, phosphate or vitamin D results are abnormal.
- To evaluate parathyroid glands, kidney disease, or bone turnover.
What sample is needed?
A healthcare professional collects a venous blood sample. Depending on the method, the laboratory uses serum or plasma.
How should you prepare?
Tell the laboratory about all medicines, hormone treatments, vitamins and supplements you take. Do not stop or change treatment unless your clinician tells you to. Follow any instructions about fasting and the time of collection.
How should you understand the result?
PTH should be interpreted simultaneously with calcium, phosphorus, vitamin D, and renal function; the same value can have different meanings in different contexts. Your result is interpreted using the reference interval on the laboratory report and in the context of your symptoms, medical history and other test findings.
Sources and editorial status
This patient-facing text is an editorial draft. It should be approved by a laboratory physician before official publication.