24-Hour Vanillylmandelic Acid (VMA) Urine Test
This test measures the amount of vanillylmandelic acid (VMA), a breakdown product of certain hormones produced by the adrenal glands, over a 24-hour period in your urine. It helps assess adrenal gland function, particularly in conditions like neuroblastoma or pheochromocytoma.
["This test helps diagnose or monitor adrenal-related hormone imbalances by tracking hormone metabolites in urine over a full day."]
Key facts at a glance
- LOINC
- 3122-9
- Short code
- VMA 24h Ur-mRate
- Synonyms
- VMA 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 This Test Is Done
Your doctor may order a 24-hour VMA urine test if they suspect an adrenal gland tumor (such as neuroblastoma or pheochromocytoma), an overproduction of certain hormones, or other conditions affecting adrenal function. It’s also used to monitor treatment progress for these conditions.
What to Expect Before the Test
You’ll need to collect all urine for a full 24-hour period, typically starting after midnight on one day and ending just before midnight the next. Follow your doctor’s instructions carefully to ensure accurate results. Wear a collection container and keep track of all urine output.
What to Expect During the Test
No special preparation is needed beyond collecting urine over 24 hours. Your sample will be sent to a lab for analysis. The test is painless and involves no invasive procedures.
What to Expect After the Test
After completing the urine collection, your sample will be processed in the lab. Results may take several days to weeks, depending on lab workload. Follow-up with your doctor if they schedule additional testing or monitoring.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Elevated VMA levels may indicate excess catecholamine production (e.g., from adrenal tumors) or other metabolic conditions. Low levels might suggest adrenal insufficiency or other hormonal imbalances. This test is critical for diagnosing rare but serious conditions affecting adrenal function and hormone regulation.
Short name
VMA Urine Test (24-hour)
Frequently asked questions
How is the VMA test different from a 24-hour urine catecholamine test?
Can I drink alcohol before the VMA test?
How long does it take to get results from a VMA urine 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