Clonidine suppression test : Sensitivity and Specificity
This is test is used to confirm a positive result of increased catecholamines in plasma or urine.
The clonidine suppression test is used to distinguish between pheochromocytoma and false-positive increases in plasma catecholamines and fractionated metanephrines.
Clonidine suppresses the release of catecholamines from neurons but does not affect the catecholamine secretion from a pheochromocytoma. (UpToDate)
Accuracy not specified