Vanillylmandelic Acid Urine Test

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Latest Edit: Hector 2014-03-21 (EDT)

See Also Lab Tests

This is a 24-hour urine test that is performed to diagnose hypertension secondary to pheochromocytoma. It is used to detect the presence of neuroblastomas and other rare adrenal tumors.[1]


  • VMA is the product of catabolism of both metanephrine and normetanephrine
  • In a pheochromocytoma, or tumor of the chromaffin cells within the adrenal medulla, one or all of these substances will be present in excessive quantities in a 24-hour urine collection.
  • VMA is more easily detected due to the concentration being higher than any one catecholamine component

Patient Preparation

  • Dietary restrictions may be required
  • Factors which can cause increased levels:
  • certain foods such as tea, coffee, cocoa, vanilla, chocolate, cider vinegar, soda, licorice, vigorous exercise, stress, starvation
  • Drugs: caffeine, epinephrine, levodopa, lithium, nitroglycerin
  • Factors which can cause decreased levels:
  • uremia, alkaline urine, and radiographic iodine contrast agents
  • Drugs: clonidine, disulfiram, guanethidine, imipramine, monoamine oxidase (MAO) inhibitors, phenothiazines, reserpine

Clinical Implications

High levels indicate:

Low levels indicate:

  • None indicated

Associated Tests

  • Pheochromocytoma suppression and provocative tests


  1. Pagana Kathleen D, Pagana Timothy J (2006) Mosby's Manual of Diagnostic and Laboratory Tests, Mosby.