Urinary Vanillylmandelic Acid (VMA) with 24-Hour Collection
This test measures the amount of vanillylmandelic acid (VMA), a breakdown product of certain hormones, in your urine over a 24-hour period. It helps assess whether your body is producing too much of these hormones, which can be linked to conditions like pheochromocytoma or neuroblastoma.
["Helps diagnose or monitor conditions affecting hormone production in the adrenal glands or nervous system."]
Key facts at a glance
- LOINC
- 93750-8
- Short code
- MuV RNA and N gene Pnl Spec
- Synonyms
- MuV RNA and N gene Pnl Spec
- 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 they suspect you have a rare tumor (such as pheochromocytoma) that produces excess hormones, or if you have symptoms like high blood pressure, headaches, sweating, or irregular heartbeat. It may also be used to monitor treatment for conditions linked to hormone imbalances.
How the Test Works
You’ll collect all your urine for a full 24-hour period in a special container. The test measures the total VMA in your urine, which reflects hormone breakdown over time. This method provides a more accurate picture than a single urine sample.
Sample Collection Process
You’ll start collecting urine immediately after waking up. Empty your bladder first, then collect every drop for the next 24 hours. Store the urine in a cool place and return it to your lab on time. Follow your provider’s instructions carefully to ensure accurate results.
What to Expect Before the Test
No special preparation is needed, but avoid certain medications (like some blood pressure drugs) that could affect results. Drink plenty of water to help flush hormones into your urine. If you’re pregnant or have kidney issues, let your provider know.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Elevated VMA levels may indicate overproduction of catecholamines (like adrenaline and noradrenaline), often linked to tumors in the adrenal glands or nervous system. Low levels might suggest other hormonal or metabolic conditions. This test is critical for diagnosing or managing conditions that require precise hormone monitoring.
Short name
24-Hour VMA Urine Test
Frequently asked questions
What does a high or low result mean?
How often will I need this test?
Can I drink alcohol before the 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