Vanillylmandelic Acid, Urine Creatinine Ratio Unit Converter

Vanillylmandelic acid (VMA) is the final breakdown product of the catecholamines epinephrine (adrenaline) and norepinephrine (noradrenaline). These hormones are released by the adrenal glands during physical or emotional stress as part of the "fight or flight" response.

The VMA/creatinine ratio measures VMA levels in a random urine sample, normalized to creatinine to account for urine concentration. This ratio provides a convenient alternative to a 24-hour urine collection while still reflecting catecholamine metabolism.

This marker is most commonly used to screen for and monitor catecholamine-secreting tumors such as neuroblastoma (especially in children) and pheochromocytoma.

VMA is produced throughout the body as the final metabolic breakdown product of epinephrine and norepinephrine. These catecholamines are made primarily in the adrenal medulla (the inner portion of the adrenal glands) and in sympathetic nerve endings, then metabolized in the liver before being excreted in urine.