Skip to content

Parathyroid Hormone (Intact)

Published: August 9, 2026Updated: August 16, 2026

This test measures the total amount of parathyroid hormone (PTH) in your blood, including the full-length active protein. PTH helps regulate calcium and phosphate levels in your body.

Quick summary

["PTH levels help diagnose and monitor conditions affecting calcium balance."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
40303-0
Short code
GH 1h p Arg SerPl-mCnc
Synonyms
GH 1h p Arg SerPl-mCnc
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
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 This Test Might Be Ordered

Your healthcare provider may recommend this test if you have symptoms like bone pain, frequent fractures, muscle weakness, or unexplained kidney stones. It may also be used to check for conditions such as hypoparathyroidism (low PTH), hyperparathyroidism (high PTH), or kidney disease that affects calcium metabolism.

What to Expect Before the Test

No special preparation is needed for this blood test. You may have a small needle inserted into your arm to draw blood, which usually causes only minor discomfort. If you’re on blood thinners, let your provider know before the test.

What the Test Results Mean

Results are interpreted by your healthcare provider based on your overall health, symptoms, and other test results. Very high or very low PTH levels can indicate underlying health issues that need further evaluation.

Common Conditions Affecting PTH Levels

High PTH levels might suggest overactive parathyroid glands (hyperparathyroidism), while low levels could indicate problems like vitamin D deficiency, kidney disease, or autoimmune disorders affecting PTH production.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

Intact PTH

Frequently asked questions

What causes PTH levels to be too high?
High PTH levels are often linked to overactive parathyroid glands (hyperparathyroidism), which can occur due to genetic factors, kidney disease, or certain cancers. Lifestyle factors like vitamin D deficiency or long-term use of certain medications may also play a role.
What causes PTH levels to be too low?
Low PTH levels can result from conditions like hypoparathyroidism (autoimmune destruction of parathyroid glands), kidney failure, or severe vitamin D deficiency. Rarely, it may occur after surgery or trauma affecting the parathyroid glands.
How often should I get this test?
Your provider will determine how often you need this test based on your health status, symptoms, and treatment plan. For example, people with kidney disease or hyperparathyroidism may need regular monitoring, while others may only need it once or twice a year.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

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.

Medical Disclaimer

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