Cortisone (U2 +2 Hours) Test

The first hour or two after you wake up is the busiest window of your stress hormone system. Your body produces a sharp morning rise in cortisol, then quickly converts much of it into an inactive form called cortisone. How that conversion is going, two hours into your day, says something useful about whether your stress hormone machinery is overdriven, exhausted, or running smoothly.

This test catches that exact moment. It measures cortisone (the inactive partner of cortisol) in dried urine collected roughly two hours after waking. Read alongside cortisol from the same sample and the other timepoints in the day, it gives you a more detailed picture of stress hormone activity than a single blood draw can.

What This Test Is Actually Measuring

Cortisol is your main stress hormone. Cortisone is its inactive twin. Your body switches between them using two enzymes (11-beta-HSD1 and 11-beta-HSD2) that turn cortisol into cortisone and back again, depending on which tissue is doing the switching. In the kidney, the enzyme converts cortisol to cortisone before the hormones are filtered out, which is why urine cortisone is high relative to urine cortisol.

Because this test uses dried urine rather than blood, it captures the free, unbound fraction of cortisone (the form that has been filtered by the kidneys). Blood-based cortisol tests largely measure the bound form, which behaves differently and is affected by binding proteins. The U2 sample, taken two hours after waking, sits after the natural morning surge in cortisol production, so it reflects how your system is returning toward baseline after that early peak.

Why the Morning Window Matters

Your stress hormone system runs on a strict daily clock. Cortisol peaks within 30 to 45 minutes of waking, a pattern called the cortisol awakening response. Cortisone tends to track cortisol but with its own dynamics, since the conversion between them is tissue-specific and time-dependent. The two-hour mark is a useful checkpoint because it captures how briskly your system is moving from peak output toward the slower afternoon and evening rhythm.

A high U2 cortisone reading can suggest your system produced a lot of cortisol in the morning and your tissues are actively inactivating it. A low reading at this timepoint can mean either reduced cortisol production overall, faster clearance, or altered enzyme activity. The interpretation depends on what cortisol is doing in the same sample and how the full daily pattern looks.

What Cortisone Levels May Signal

Cortisone in urine largely reflects how much cortisol your body is producing and how aggressively your kidneys and other tissues are inactivating it. The cortisol-to-cortisone ratio at any given timepoint reports on enzyme activity. Patterns of high or low cortisone across multiple timepoints can indicate sustained stress, blunted adrenal output, or atypical hormone metabolism.

This is a research and functional-medicine marker rather than a guideline-recommended diagnostic test. Standardized clinical cutpoints for U2 dried urine cortisone do not exist. A single number is most useful when read together with cortisol at the same timepoint, the rest of the day's samples, and the full clinical picture.

Stress and HPA Axis Activity

The hypothalamic-pituitary-adrenal axis (HPA axis, your body's central stress-response system) is the engine behind cortisol and cortisone. Studies using blood, saliva, or 24-hour urine collection (which capture different fractions than this dried urine timepoint) have linked sustained HPA overactivity to depression, type 2 diabetes, metabolic syndrome, and cognitive decline. Studies have also linked reduced HPA activity to fatigue, post-traumatic stress disorder, and burnout patterns.

Whether this specific U2 dried urine cortisone measurement reproduces these associations has not been studied with the same rigor. What it can show is whether your morning cortisone output is unusually high or low compared with your own readings over time, which is a more useful question than absolute thresholds.

Cortisol Excess Patterns

In conditions where cortisol production runs persistently high (autonomous cortisol secretion from adrenal nodules, Cushing's syndrome, or chronic glucocorticoid medication use), studies using 24-hour urinary free cortisol and salivary cortisone show elevated values. Salivary cortisone after a dexamethasone suppression test, for example, identifies most cases of autonomous cortisol secretion with high specificity. Whether the U2 dried urine cortisone reading shifts in the same direction is plausible but not directly tested in the available research.

If your U2 cortisone is markedly elevated alongside elevated cortisol at multiple timepoints, that pattern is worth investigating with established clinical tests rather than acting on the dried urine number alone.

Cortisol Deficiency Patterns

When the adrenal glands produce less cortisol (primary adrenal insufficiency, secondary adrenal insufficiency from pituitary issues, or chronic suppression from long-term steroid use), cortisone output also drops. The strongest evidence for this comes from salivary and blood-based studies. In a study of home waking salivary cortisone, this measurement identified adrenal insufficiency with accuracy comparable to a clinic-based stimulation test (AuROC 0.95, which means it correctly distinguished cases from non-cases 95% of the time).

Low U2 cortisone alongside low cortisol across the day is consistent with reduced adrenal output, but confirming adrenal insufficiency requires a morning serum cortisol and, in most cases, an ACTH stimulation test (which directly measures the gland's ability to respond).

Metabolic and Tissue-Level Effects

The enzyme that activates cortisone back into cortisol (11-beta-HSD1) is unusually active in fat tissue and liver in people with obesity and type 2 diabetes. This local reactivation contributes to insulin resistance and steatosis (fat buildup in the liver). Blood and tissue studies show this clearly. The signal in dried urine is less direct, but a high cortisone-to-metabolized-cortisol pattern can hint at altered enzyme activity worth investigating with metabolic labs.

Reference Ranges and How to Read Yours

There are no published, universally accepted clinical cutpoints for U2 dried urine cortisone. The available reference values come from the lab that runs the assay (typically using liquid chromatography mass spectrometry) and are derived from a population of asymptomatic adults rather than from outcome studies tying specific numbers to disease risk.

Treat any range your lab reports as orientation, not a target. The most useful comparison is your own value over time, run by the same lab using the same method. A value that is markedly outside the lab's range, alongside a similarly abnormal cortisol pattern across the day, is more meaningful than a value that is slightly off in isolation.

Why One Reading Is Not Enough

Cortisone, like cortisol, varies day to day. A poor night of sleep, a recent illness, an unexpected stressor, or a deviation in collection technique can all shift a single reading. The signal that matters is the pattern, not the point. That means at least two collections done under similar conditions before drawing any conclusions, and serial tracking if you are making changes you expect to influence stress hormone biology.

A reasonable cadence is to get a baseline four-point profile, retest in 3 to 6 months if you are making meaningful lifestyle, sleep, or treatment changes, and then annually for ongoing tracking. If your first result is very abnormal and you have suggestive symptoms, retest within 4 to 8 weeks to confirm before acting on the number.

What to Do With an Abnormal Result

Treat this test as a signal to investigate, not a diagnosis. If your U2 cortisone is high and your cortisol at the same timepoint is also high, the pattern points toward HPA overactivity or possible cortisol excess. Useful follow-up tests include a morning serum cortisol, 24-hour urinary free cortisol, late-night salivary cortisol, ACTH, and a dexamethasone suppression test. Endocrinology consultation is warranted if multiple tests suggest autonomous cortisol secretion or Cushing's spectrum disease.

If your U2 cortisone is low and your cortisol pattern is also flat across the day, ask about a morning serum cortisol and DHEA-sulfate first. A morning serum cortisol below typical lab thresholds, or symptoms consistent with adrenal insufficiency (chronic fatigue, low blood pressure, salt craving, unexplained weight loss), warrants an ACTH stimulation test. If both cortisol and cortisone are normal but the cortisol-to-cortisone ratio is unusual, that points more toward altered enzyme activity than toward a primary adrenal problem.

When Results Can Be Misleading

• Collection timing errors: the U2 sample must be collected approximately two hours after the U1 waking sample. Collecting too early misses the post-peak recovery period; collecting too late catches the natural decline and produces a falsely low reading.
• Shift work and irregular sleep: if your wake time varies widely or you work overnight shifts, the morning hormone rhythm is shifted or blunted. Standard reference ranges, which assume a conventional sleep schedule, may not apply.
• Recent acute illness or unusual stress: an intercurrent infection, surgery, or major emotional event in the days before collection can transiently push cortisol and cortisone up. Wait until you are back to baseline before testing.
• Corticosteroid medications: oral, inhaled, topical, or injected steroids (including prednisone, hydrocortisone, dexamethasone, and high-dose inhalers) suppress your body's natural cortisol production and can lower cortisone output for days to weeks after the dose. Note all steroid exposure when interpreting results.