Vanillylmandelic Acid, Urine Random Unit Converter

Vanillylmandelic acid (VMA) is the major end-stage breakdown product of the catecholamines epinephrine (adrenaline) and norepinephrine (noradrenaline). When your body produces and uses these stress hormones, they are metabolized in the liver and excreted in the urine as VMA.

A random urine VMA test measures the concentration of VMA in a single spot urine sample, normalized to creatinine. This is a convenient alternative to the traditional 24-hour urine collection, and is especially useful in children.

VMA is most commonly measured alongside homovanillic acid (HVA) and metanephrines to help detect tumors that secrete excess catecholamines, such as pheochromocytoma and neuroblastoma.

VMA is produced in the liver as the final breakdown product of epinephrine and norepinephrine. These catecholamines originate from the adrenal medulla and sympathetic nerve endings throughout the body.