VMA (Vanillylmandelic Acid) 24-Hours Urine is a test that measures the amount of VMA, a metabolite of catecholamines (adrenaline and noradrenaline), excreted in the urine over a 24-hour period. It is used to assess the function of the adrenal glands, particularly to diagnose pheochromocytoma (a rare adrenal tumor) or neuroblastoma (a type of cancer). Elevated VMA levels can indicate these conditions, as they are associated with increased production of catecholamines. This test is often used to evaluate individuals with high blood pressure, headaches, or other symptoms related to adrenal gland disorders.