Parathyroid Hormone, Active (Active PTH)
This test measures the active form of parathyroid hormone (PTH), a key regulator of calcium and bone metabolism.
["Active PTH helps balance calcium levels in your body and supports bone health."]
Key facts at a glance
- LOINC
- 12799-3
- Short code
- PTH Ab Ser-aCnc
- Synonyms
- PTH Ab Ser-aCnc
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 0.8
- Ref high
- 1.2
- Critical range
- — – 5 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 85610
- SNOMED
- 396252006
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
Why Is This Test Done?
Your doctor may order an active PTH test to diagnose or monitor conditions affecting calcium levels, such as hypoparathyroidism, hyperparathyroidism, or kidney disease. It can also help assess bone health or evaluate symptoms like muscle weakness, confusion, or abnormal heart rhythms.
What Does Active PTH Tell You?
High levels may suggest overactive parathyroid glands or kidney problems, while low levels could indicate underactive glands or other metabolic disorders. This test helps guide treatment decisions for conditions like osteoporosis or calcium imbalances.
How Is the Test Performed?
A blood sample is taken from a vein in your arm. The sample is sent to a lab where the active PTH level is measured using a specialized immunoassay method.
What Are Common Results?
Results are not provided with specific reference ranges, as they vary by lab and patient factors. Your doctor will interpret the results in relation to your symptoms and medical history.
Reference range
INR: 0.8-1.2 (warfarin: 2.0-3.0)N/A
Inform your healthcare provider if you are taking blood thinners. No special preparation required.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical Significance: Active PTH plays a critical role in maintaining calcium homeostasis. Abnormal levels can indicate underlying disorders affecting bone, mineral metabolism, or kidney function, requiring medical evaluation and potential treatment adjustments.
Short name
Active PTH
Frequently asked questions
What causes abnormal active PTH levels?
How long does it take to get results?
Can diet or supplements affect active PTH levels?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy