Skip to content

Serum or Plasma Free Metanephrine

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

This test measures the amount of a natural chemical called metanephrine in your blood, which helps your body respond to stress. It’s used to check for conditions like pheochromocytoma, a rare tumor that can cause high blood pressure and other symptoms.

Quick summary

["This test helps diagnose rare but serious conditions affecting your adrenal glands."]

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

Key facts at a glance

LOINC
109229-5
Short code
PSA Free Msmt Smn
Synonyms
PSA Free Msmt Smn
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Ref low
0
Ref high
4
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
CPT
84153
SNOMED
39392002
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 this test if you have symptoms like severe headaches, rapid heartbeat, high blood pressure, or unexplained sweating. It’s often used alongside other tests to confirm conditions like pheochromocytoma or other adrenal tumors.

What Does the Test Measure?

Metanephrine is a breakdown product of a hormone called norepinephrine. High levels may indicate overproduction of these hormones, which can cause dangerous health issues.

How Is the Test Performed?

A blood sample is taken from a vein in your arm. The sample is sent to a lab where it’s analyzed using a sensitive immunoassay method to detect free metanephrine levels.

What Are Common Results?

Results are reported as a concentration value (in micrograms per liter or another unit). Your doctor will compare these results to your symptoms and other tests to determine if further action is needed.

Reference range

Normal: <4.0 ng/mLN/A

Specimen: serum

No special preparation required. For PSA, avoid sexual activity for 24-48 hours before the test.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Clinical Significance: This test is critical for diagnosing pheochromocytoma and other adrenal-related conditions. Abnormal results may require additional imaging or follow-up tests to guide treatment, such as medication or surgery.

Short name

Free Metanephrine

Frequently asked questions

What causes high or low metanephrine levels?
High levels are often linked to tumors (like pheochromocytoma) or other adrenal gland disorders. Low levels are less common but may occur with certain genetic conditions or adrenal insufficiency.
How long does it take to get results?
Results are typically available within 1–3 business days, depending on lab processing times.
Can I eat or drink before this test?
You may need to fast for 8–12 hours before the test, but your doctor will provide specific instructions based on your situation.
  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