24-Hour Urinary Vanillylmandelic Acid (VMA) Rate
This test measures how much vanillylmandelic acid (VMA) your body excretes in urine over 24 hours. It helps assess whether certain nerve cells in your body are functioning properly.
["VMA helps detect issues with adrenal or sympathetic nerve function."]
Key facts at a glance
- LOINC
- 2436-4
- Short code
- HVA 24h Ur-mRate
- Synonyms
- HVA 24h Ur-mRate
- Category
- chemistry
- Sample
- urine
- Container
- Sterile urine container
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Specimen volume
- 10 mL
- Stability
- Room temperature: 2h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 0
- Lipemia max
- 0
- Icterus max
- 0
- TAT
- 4–24 hours
- Order
- routine
Why Is This Test Done?
Your doctor may order this test if you have symptoms like headaches, high blood pressure, or unusual sweating that could suggest problems with nerve cells in your adrenal glands or nervous system. It’s also used to check for conditions like neuroblastoma (a type of cancer in children) or pheochromocytoma (a tumor affecting hormone production).
What to Expect Before the Test
You’ll need to collect all your urine for a full 24-hour period, starting and ending with your first morning urine. Store the urine in a refrigerator until you deliver it to the lab. Follow your doctor’s instructions carefully to ensure accurate results.
How the Test Works
The test measures the amount of VMA, a breakdown product of certain hormones, in your urine. High levels may indicate overactivity of nerve cells producing adrenaline or noradrenaline.
What the Results Mean
Results are compared to a reference range, but exact values can vary by lab. Elevated levels may signal conditions like pheochromocytoma or neuroblastoma, while normal levels help rule out these issues.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Elevated VMA levels can indicate excessive hormone production by adrenal glands or nerve cells, potentially causing symptoms like rapid heart rate, sweating, or blood pressure changes. This test is critical for diagnosing rare but serious conditions that require prompt treatment. Low or normal levels help confirm other diagnoses or monitor treatment effectiveness.
Short name
VMA Urine Rate
Frequently asked questions
What causes abnormal VMA levels?
How often should I get this test?
Can I take medications before this test?
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