Cortisol Urine Total

Normal 24‑hour urinary free cortisol is roughly 10–100 µg per 24 hours (≈28–276 nmol/24 h); exact reference ranges vary by laboratory and assay. Some labs use a cutoff near 50 µg/24 h. Results above the lab’s upper limit may prompt repeat testing and further assessment for Cushing’s syndrome; interpretation should consider clinical context and medications.

High urinary cortisol means your body is excreting excess free cortisol, indicating hypercortisolism. Causes include Cushing’s syndrome (pituitary, adrenal, or ectopic ACTH tumors), prolonged glucocorticoid use, or stress‑related/“pseudo‑Cushing” conditions (depression, alcohol, obesity). It raises risks—weight gain, high blood pressure, insulin resistance, bone loss—and requires confirmatory testing (repeat urine, late‑night salivary cortisol, dexamethasone suppression) and evaluation for causes.

A normal total (serum) cortisol level varies by time of day: in the early morning (around 8 AM) it's roughly 140–690 nmol/L (5–25 µg/dL), while afternoon values are lower, about 90–400 nmol/L (3–15 µg/dL). Levels are assay- and lab-specific; clinical interpretation requires correlation with symptoms, timing, and repeat testing. Ask your clinician for your lab's reference range.

Read your cortisol result against the lab’s reference range and the sample time (cortisol peaks in the morning and falls later in the day). A single high result may reflect stress, illness, or steroid use; persistently high levels suggest Cushing’s. Low results can indicate adrenal insufficiency. Abnormal values usually require repeat testing and complementary tests (ACTH, 24‑hour urine, suppression/stimulation) and clinical correlation—discuss with your clinician.

High cortisol can cause weight gain (especially around the abdomen and face), a rounded "moon" face, increased appetite, and fat redistribution. Other signs include persistent fatigue, muscle weakness, thinning skin with easy bruising and purple stretch marks, high blood pressure and blood sugar, mood changes (anxiety, depression, irritability), poor sleep, cognitive difficulties, menstrual irregularities and reduced libido.

A 24‑hour urinary free cortisol (UFC) test is useful and reasonably accurate for detecting sustained cortisol excess, but results can be skewed by incomplete collection, kidney dysfunction, high fluid intake, certain drugs, acute illness or intermittent secretion. Spot urine tests are less reliable. Creatinine correction and repeat or complementary tests (late‑night salivary cortisol, dexamethasone suppression) plus clinical correlation improve diagnostic accuracy.