The blood test for catecholamines measures the level of catecholamines in the plasma portion of blood.
Alternative Names: Norepinephrine - blood; Epinephrine - blood; Adrenalin - blood; Dopamine - blood
How the test is performed:
Catecholamines are more often measured with a urine test than with this blood test.
Blood is drawn from a vein, usually from the inside of the elbow or the back of the hand. The puncture site is cleaned with antiseptic. An elastic band is placed around the upper arm to apply pressure and cause the vein to swell with blood.
A needle is inserted into the vein, and the blood is collected in an air-tight vial or a syringe. During the procedure, the band is removed to restore circulation. Once the blood has been collected, the needle is removed, and the puncture site is covered to stop any bleeding.
In infants or young children:
The area is cleansed with antiseptic and punctured with a sharp needle or a lancet. The blood may be collected in a pipette (small glass tube), on a slide, onto a test strip, or into a small container. A bandage may be applied to the puncture site if there is any bleeding.
How to prepare for the test:
Certain foods can increase catecholamine levels including coffee, tea, bananas, chocolate, cocoa, citrus fruits, and vanilla. Avoid these foods for several days prior to the test, particularly if both serum and urine catecholamines are to be measured.
Avoid other interfering factors:
Consult your health care provider regarding the need to discontinue potentially interfering drugs. Drugs that can increase catecholamine measurements include caffeine, levodopa, lithium, aminophylline, chloral hydrate, clonidine, disulfiram, erythromycin, insulin, methenamine, methyldopa, nicotinic acid (large doses), quinidine, tetracyclines, and nitroglycerin.
Drugs that can decrease catecholamine measurements include clonidine, disulfiram, guanethidine, imipramine, MAO inhibitors, phenothiazines, salicylates, and reserpine.
Never discontinue any medication without first consulting your provider.
How the test will feel:
When the needle is inserted to draw blood, you may feel moderate pain, or only a prick or stinging sensation. Afterward, there may be some throbbing.
Why the test is performed:
This test is used primarily to screen for, diagnose, and monitor treatment of pheochromocytoma or neuroblastoma.
Catecholamines are chemically similar small molecules derived from tyrosine, an amino acid. The major catecholamines are dopamine, norepinephrine, and epinephrine (which used to be called adrenalin).
Normal value ranges may vary slightly among different laboratories.
Epinephrine: 20 ng/100 mL (ng/mL = nanograms per milliliter)
Norepinephrine: 60 ng/100 mL
What abnormal results mean:
Elevated levels of blood catecholamines may indicate the following:
Additional conditions under which the test may be performed include Shy-Drager syndrome.
What the risks are:
The test's accuracy is affected by several foods and drugs as well as such things as physical activity and stress.
Veins and arteries vary in size from one patient to another and from one side of the body to the other. Obtaining a blood sample from some people may be more difficult from some people than from others.