Website maintenance is planned from 8:00 a.m. CDT Saturday, July 27, through 9:00 p.m. CDT Sunday, July 28. Brief disruptions may occur during this time.
Recommended first-line testing is either plasma free metanephrines or urinary fractionated metanephrines. If measuring plasma metanephrines, patients should have their blood drawn while in a supine position, and the values should be compared to reference intervals determined from the same collection position.