VMA (Vanillylmandelic Acid), 24-Hour Urine

Vanillylmandelic acid (VMA) is the major urinary product resulting from the metabolic degradation of catecholamine, norepinephrine and epinephrine. Elevated concentrations of VMA are commonly found in cases of catecholamine secreting tumors such as pheochromocytoma, neuroblastoma, and ganglioneuroma.

Drugs which can interfere with testing due to physiologic response: clonidine, L-dopa, methocarbamol, monoamine oxidase inhibitors, reserpine, salicylates.