- 1mg overnight dexamethasone suppression test: order 1mg dexamethasone to pharmacy and ask patient to take it at 11 pm at night. The next AM, patient must come to the lab for a cortisol level. Results below 5 usually rule out cushing's syndrome. PLEASE ENSURE PT IS NOT ON ANY OTHER STEROIDS AT THIS TIME.
- 24 H urine metanephrines: levels >4 fold are consistent with pheochromocytoma. minimal (less than 1x above normal) elevations are very common in patients on beta blocker and other antihypertensive agents.
- 8am aldosterone and plasma renin activity, to calculate ratio: Ratio >20 with aldosterone >14 and suppressed PRA is highly suggestive of primary hyperaldosteronism.
If pt's renal function allows, please order a CT adrenal protocol with contrast to further visualize the adrenals.