Vanilmandelic acid in the urine

What is Vanilmandelic Acid?

Vanilmandelic acid is an end product of the adrenaline and noradrenaline catecholamine metabolism; consequently, its dosage in urine collected over 24 hours can identify the noradrenergic hypersecretion that characterizes tumors deriving from chromaffin tissue (pheochromocytoma / paragangliomas, neuroblastomas), or evaluate its response to the medical therapy undertaken.

Exam Preparation

The titer of vanilmandelic acid, which is high in the above conditions, is an alternative or complementary investigation to find catecholamines and their other metabolites, such as metanephrines, in urine. The only drawback derives from the influence that many substances of alimentary or pharmaceutical origin exert on the urinary excretion of vanilmandelic acid. Thus, in order not to distort the results of the test it is recommended, starting from 48-72 hours before the start of urinary collection, and for the entire duration of the collection itself, to:

• observe a diet without the following foods: avocado, banana, kiwi, dried fruit, coffee, tea, chocolate; more generally, avoid the intake of nerve foods and thermogenic supplements, such as those based on cola, caffeine, guarana, mate, and synephrine;
• avoid intense physical efforts (including physical activity) and more generally any stressful event, even on a psychological level only;
• after medical consultation, avoid taking drugs that interfere with the synthesis or release of catecholamines (for example those with sympathomimetics), with kidney function or that otherwise influence the urinary elimination of vanilmandelic acid: caffeine, tricyclic antidepressants, drugs containing catecholamines, amphetamine derivatives, nasal decongestants, acetylsalicylic acid, clonidine, chlorpromazine, diuretics, felodipine. furosemide, glyceryltrinitrate, histamine, iproniazid, levodopa, pindolol, reserpine. Consult your doctor.

Normal values