When should Cortisol be retested?

The optimal timing for retesting cortisol depends heavily on the clinical context. If an initial result is abnormal (e.g., elevated salivary, serum, or urinary cortisol), retesting should be performed under standardized conditions: morning between 7–9 AM, fasting, and after a stress-free night. For suspected Cushing's syndrome, multiple measurements (late-night salivary cortisol, 24h urine, dexamethasone suppression test) are required, often repeated weeks apart. For suspected adrenal insufficiency, an ACTH stimulation test is used, not a simple retest. Single cortisol measurements are unreliable due to pulsatile secretion and stress sensitivity. MyBody-X offers hormone tests, but interpretation must be done by a physician. Without specific symptoms or risk factors, routine retesting is not recommended. The evidence is based on clinical practice, not on the provided context.