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Plasma Free Metanephrines

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Also known as: Plasma Metanephrines
Formal name: Fractionated Plasma Free Metanephrines (Normetanephrine and Metanephrine)

At a Glance

Why Get Tested?

To help diagnose or rule out a pheochromocytoma

When to Get Tested?

When you have persistent or episodic high blood pressure and symptoms such as headaches, rapid heart rate, and sweating

Sample Required?

A blood sample drawn from a vein in your arm

Test Preparation Needed?

Preparation for the test is important for accurate results. You should discontinue epinephrine and epinephrine-like drugs for at least one week before the test, stop using acetaminophen 48 hours beforehand, and fast for 8-10 hours prior to collection. It is especially important not to have any caffeine-containing food (soda, chocolate), coffee (including decaf), tobacco (smoking cigarettes or cigars), tea, or alcohol for at least 4 hours before specimen collection. Talk to your doctor about all the medications you are taking as well since several different drugs may interfere with the test.