Parathyroid hormone (PTH)
PTH test · parathyroid hormone · intact PTH
This is a blood test from a vein. It shows the level of the hormone that controls calcium in your blood and bones.
For changes in blood calcium, kidney disease, osteoporosis, or kidney stones.
⏱ Duration: the blood draw takes a few minutes; results usually come in 1 to 3 days
Be sure to tell your doctor
How to prepare
- Time and food. Usually in the morning, fasting for 8 to 12 hours. Water is fine.
- The day before. For 24 hours, no alcohol and no hard workouts. Best not to smoke in the morning.
- Medicines. Do not stop them on your own. Tell your doctor what you take. They will decide if anything should change.
What to bring
- Your test request form
- Your ID
- Past calcium and vitamin D tests, if you have them
How it goes
- You sit down and rest your arm on the armrest
- A band is tightened above your elbow
- The skin is wiped with antiseptic
- A quick prick, and blood fills a tube
- The needle comes out, and a cotton pad is pressed on the spot
What you'll feel
- A quick prick, like a pinch
- Sometimes slight dizziness. Tell the nurse
Afterwards
- Press the cotton pad for 3 to 5 minutes and keep your arm straight
- You can eat right away and go back to your usual day
- Calcium and vitamin D are often tested together with PTH
- Results usually come in 1 to 3 days. The lab will tell you when
Common questions
Why is calcium tested together with PTH?
Your doctor looks at these numbers together. On their own, they say less.