The biochemical diagnosis of adrenal insufficiency with modern cortisol assays: Reappraisal in the setting of opioid exposure and hospitalization.

Applying a cutoff of <405 nmol/L (14.7 µg/dl), opioid-induced adrenal insufficiency is rare. Nearly 1 out of 6 patients would be reclassified as having adrenal insufficiency applying the guideline-recommended cutoff of <500 nmol/L (18.1 µg/dl). Serum morning cortisol <83 nmol/L (3 µg/dl) is not a valid diagnostic test for adrenal insufficiency in hospitalized patients, whether or not receiving opioids.