- Blood cortisol can be estimated randomly (Random Cortisol) or multiple times as requested by the physician.
- Blood sample for serum cortisol tests are to be drawn at around 8 AM (7:30 am to 8:30 am) for cortisol – morning, when cortisol is at its peak, and at around 4 PM (3:30 pm to 4:30 pm), when the levels should have dropped. Sometimes a resting sample is obtained late in the evening.
- When the physician requests for a urine cortisol, 24 hrs urine sample or a single first morning urine sample needs to be collected based on the physician’s advice.
