Urinary Vanillylmandelic Acid (VMA) or Metanephrines (total)

What Does This Test Measure?

Your urine contains natural chemicals called catecholamines (like adrenaline and noradrenaline) and their breakdown products, including vanillylmandelic acid (VMA) and metanephrines. These substances are produced by the adrenal glands and nerves. Elevated levels may signal tumors or other conditions affecting these areas.

Why Might This Test Be Ordered?

Your doctor may recommend this test if you have symptoms like severe headaches, high blood pressure, rapid heartbeat, or unexplained weight loss. It’s also used to check for conditions like pheochromocytoma (a tumor in the adrenal glands) or neuroblastoma (a childhood cancer affecting nerves).

How Is the Test Performed?

You’ll collect a 24-hour urine sample, starting after midnight on one day and ending just after midnight the next. The sample is sent to a lab for analysis using sensitive methods like chromatography or immunoassay to measure these chemicals.

What Are Possible Results?

Results are compared to reference ranges for healthy individuals. High levels may indicate abnormal production of these chemicals, while low levels might suggest other health concerns. Your doctor will interpret the results in the context of your symptoms and medical history.