The abbreviation VMA refers to which compound?

• A. Vanillylmandelic acid
• B. Metanephrine
• C. Catecholamine
• D. Epinephrine

Answer: (A)

VMA stands for vanillylmandelic acid, the urinary end product of catecholamine metabolism. When adrenaline and noradrenaline are broken down, they are first converted to metanephrines and then oxidized to vanillylmandelic acid, which is excreted in urine. Clinically, measuring VMA helps detect excess catecholamines from tumors like pheochromocytoma. It’s not the active catecholamines themselves nor their intermediate metabolite metanephrine, which is why vanillylmandelic acid is the correct designation.