Abstract
Physicians from many specialities frequently require cortisol analyses from biochemical laboratories, not just endocrinologists. Measuring relevant cortisol levels and differentiating between cortisol insufficiency and normal functioning of the hypothalamic-pituitary-adrenal axis is crucial, and requires the observance of several rules in the pre-analytic phase including blood collection.
In particular, the circadian profile of cortisol, food intake, as well as the blood drawing itself as a possibly stressful event all have to be taken into account when a cortisol blood test is scheduled. Additionally, blood collection should be avoided in the first hour after awakening, and a proper analytic method has to be selected.