High Morning Cortisol: Stress or Cushing's?

Short Answer

Morning cortisol can rise with stress and anxiety, pregnancy, estrogen-containing medicines, obesity, depression or alcohol use. According to the TEMD (Society of Endocrinology and Metabolism of Turkey) 2025 Adrenal guideline, a single morning cortisol has quite limited value in diagnosing Cushing's syndrome. When Cushing's is suspected, the 1 mg dexamethasone suppression test, late-night salivary cortisol or 24-hour urine cortisol is used. Evaluate your result together with the laboratory reference range on your report.

How does it appear on your report?

On reports, cortisol tests are listed separately according to the sample type and time:

• Blood: "Cortisol", "Cortisol morning measurement" or "Cortisol midnight measurement".
• Saliva: "Cortisol (Saliva)"; usually collected late at night.
• Urine: "Free cortisol (24-hour urine)".

In the Turkish Ministry of Health's Test Measurement Units list, blood and salivary cortisol appear in µg/dL, and 24-hour urine free cortisol in µg/24 hours. Guidelines also use nmol/L. For example, 1.8 µg/dL corresponds to 50 nmol/L.

The "My Test Results" (Tahlillerim) screen in e-Nabız (Türkiye's national health record app) shows the result together with its reference value and marks out-of-range values in color. Using the graph icon, you can compare it with your previous results.

Why does the time matter? Cortisol has a daily rhythm; in a healthy person it falls to its lowest level at night. The morning range on the report is for blood drawn in the morning. Comparing a sample taken in the afternoon with this range is misleading.

Range or threshold? The value given for morning cortisol is a reference range. The 1.8 µg/dL in the 1 mg dexamethasone test, however, is a decision limit. Under the Ministry of Health procedure, decision limits may be marked with an asterisk (*) on the report.

Normal value and reference range

Cortisol ranges vary by laboratory and measurement method. The table below shows the thresholds mentioned in guidelines.

Test	Threshold or range	What does it mean?	Source
Morning serum cortisol (08–09)	Specific to the laboratory and method	Limited value on its own in diagnosing Cushing's	TEMD 2025
Morning cortisol after 1 mg dexamethasone	Below 1.8 µg/dL (50 nmol/L)	Normal suppression; Cushing's most likely absent	TEMD 2025; Pituitary Society 2021
Same test, without symptoms	Above 1.8 µg/dL	Mild autonomous cortisol secretion in an adrenal mass	ESE 2023; TEMD 2025
Late-night salivary cortisol	Method-specific upper limit	At least 2–3 samples recommended	Pituitary Society 2021
24-hour urine free cortisol	Method-specific upper limit	Collection on 2–3 separate days recommended	Pituitary Society 2021; TEMD 2025
Basal morning cortisol (for low cortisol)	18 µg/dL and above	Largely rules out adrenal insufficiency	TEMD 2025

According to TEMD 2025, with newer methods (LC-MS/MS and monoclonal assays) this last threshold is taken as 13–14 µg/dL. The reference range covers 95% of healthy people; about 1 in 20 healthy people may fall slightly outside the range.

What does a high value mean?

The causes are listed from common and harmless to rare and serious.

1. Time of blood draw and stress. According to the Ministry of Health's 2024 guide, mental stress such as anxiety before the blood draw increases cortisol secretion. Caffeine can also raise free cortisol in serum. Such elevations are usually temporary.

2. Increase in carrier protein. According to TEMD 2025, cortisol-binding globulin increases in pregnancy and in people taking oral estrogen (for example, birth control pills). In this case, total cortisol may be measured higher than it really is.

3. Excess cortisol not due to Cushing's (formerly called pseudo-Cushing's). According to the Pituitary Society 2021 consensus, psychiatric disorders, alcohol use disorder, polycystic ovary syndrome and obesity can stimulate the cortisol axis. In these people, screening tests may also be mildly abnormal. Urine cortisol, however, almost always stays below 3 times normal. TEMD 2025 also adds sleep-wake rhythm disorders to this group.

4. Cortisone-type medicines. According to TEMD 2025, the most common cause of Cushing's syndrome is glucocorticoids taken from outside the body. In someone with a Cushingoid appearance, a very low blood cortisol suggests this cause. Some medicines can also affect the result through cross-reactivity in the assay.

5. Endogenous Cushing's syndrome. This is the body's own excess cortisol production and is rare. According to data cited by TEMD 2025, its annual incidence is 1.8–3.2 per million. Excluding ectopic causes, it is reported at least 4 times more often in women. Its causes are a pituitary tumor (Cushing's disease), an adrenal tumor, or ACTH secretion by another tumor. Wide purple stretch marks on the abdomen, easy bruising, thin skin and weakness in the hip and shoulder muscles are more meaningful findings. Osteoporosis or high blood pressure at a young age also raises suspicion.

When read together

• High morning cortisol + normal 1 mg dexamethasone test: According to TEMD 2025, a value below 1.8 µg/dL rules out endogenous excess with more than 99% certainty.
• 1.8–5 µg/dL after 1 mg dexamethasone: Can be seen in obesity, chronic psychiatric problems and sleep disorders. Above 5 µg/dL is more associated with true excess.
• Two different screening tests abnormal: According to the Endocrine Society 2008 guideline, the next step is tests aimed at finding the cause.
• Confirmed Cushing's + ACTH below 10 pg/mL: Suggests an adrenal source. ACTH above 20 pg/mL, on the other hand, is consistent with an ACTH-dependent picture.
• Cushingoid appearance + very low blood cortisol: A cortisone-type medicine taken from outside the body comes to mind.
• High cortisol + birth control pill use: The elevation may be partly due to an increase in carrier protein.

Preparing for the test

• Time: For morning cortisol, blood is drawn between 08:00 and 09:00. The Ministry of Health guide also recommends drawing routine blood between 07:00 and 09:00 in the morning.
• Caffeine and smoking: On the morning before the blood draw, avoid tea, coffee and smoking.
• Be rested: Arriving in a hurry, stressed or sleep-deprived can affect the result.
• Medicines: If you use birth control pills, or a cortisone cream, spray, inhaler or injection, tell your physician. According to TEMD 2025, after a cortisone injection into a muscle or joint, waiting 4 weeks is recommended before measuring basal cortisol. Do not stop your medicine on your own.
• 1 mg dexamethasone test: The medicine your physician gives you is taken at around 11:00 p.m.; blood is drawn the next morning between 08 and 09.
• Saliva test: Collect the sample at your usual bedtime. If you work night shifts or have severe gum disease, this test is not suitable.
• 24-hour urine: Collect all urine without missing any. If your creatinine clearance is below 60 mL/min or you pass more than 5 liters of urine a day, the saliva test may be preferred.

Which doctor, which test?

• First step: Family physician or internal medicine specialist; medication and stress history are evaluated.
• Endocrinology: If there are signs of Cushing's, a screening test is abnormal, or an adrenal mass has been found incidentally.
• Screening tests: 1 mg dexamethasone suppression test, late-night salivary cortisol or 24-hour urine free cortisol.
• Investigating the cause: Once the diagnosis is confirmed, ACTH is measured; then adrenal or pituitary imaging is planned.
• Adrenal mass: According to the ESE 2023 guideline, every patient undergoes a 1 mg dexamethasone test.
• Mental health and sleep: If there is depression, alcohol use or a sleep problem, see the relevant specialist.

In Türkiye

• National guideline: The current edition of the TEMD Adrenal and Gonadal Diseases Guideline is dated 2025. It uses the 1.8 µg/dL threshold for the 1 mg dexamethasone test in Cushing's screening.
• Test items: In the Ministry of Health unit list, morning and midnight blood cortisol appear as separate tests. So check the test name and blood draw time on your report.
• Sampling rules: The Ministry of Health's Medical Biochemistry Total Testing Process Guide (2024) states that stress and caffeine can affect cortisol.
• Medication-related Cushing's: TEMD 2025 recommends that people taking cortisone-type medicines be monitored for medication-induced Cushing's.
• Articles on lowering cortisol: Stress management advice can be helpful. However, this advice does not replace test interpretation or a diagnosis of Cushing's.

When should I seek emergency care?

• If you have sudden shortness of breath, chest pain or one-sided leg swelling, call 112 (the emergency number in Türkiye). According to TEMD 2025, the tendency to form blood clots is increased in Cushing's syndrome.
• If you suddenly stopped cortisone after taking it for a long time and are experiencing weakness, vomiting or fainting, call 112.
• If you have a high fever or signs of a serious infection, go to the emergency department the same day; susceptibility to infection is increased in Cushing's.
• If you have excessive thirst, very frequent urination and confusion, go to the emergency department the same day.
• If you have severe depression, loss of touch with reality or thoughts of harming yourself, call 112.
• If the laboratory has called you about a critical value, see your physician or go to the emergency department the same day.

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• High parathyroid hormone (PTH) and bone health
• How to lower cortisol: a stress hormone guide
• Stress, belly fat and sleep
• Chronic stress, cortisol and memory

What changed? (October 2026)

• Aligned with the 2025 edition of the TEMD Adrenal and Gonadal Diseases Guideline.
• The 1.8 µg/dL threshold from the Pituitary Society 2021 consensus and the ESE 2023 adrenal mass guideline was added.
• The ESE 2023 concept of "mild autonomous cortisol secretion" was used.

Sources

• Türkiye Endokrinoloji ve Metabolizma Derneği (TEMD). Adrenal ve Gonadal Hastalıklar Kılavuzu. 2025. https://file.temd.org.tr/Uploads/publications/guides/documents/AdrenalKilavuz2025.pdf (accessed October 2, 2026)
• T.C. Sağlık Bakanlığı SHGM. Tıbbi Biyokimya Toplam Test Süreci Rehberi, Publication No. 1287. May 2024. https://dosyamerkez.saglik.gov.tr/Eklenti/48692/0/tibbi-biyokimya-toplam-test-sureci-rehberipdf.pdf (accessed October 2, 2026)
• T.C. Sağlık Bakanlığı SHGM. Test Ölçüm Birimleri, Versiyon 2. 15.09.2021. https://dosyamerkez.saglik.gov.tr/Eklenti/41467/0/test-olcum-birimleri-versiyon-2-pdfpdf.pdf (accessed October 2, 2026)
• T.C. Sağlık Bakanlığı SHGM. Karar Sınırı, Kritik Değer ve Ölçüm Birimlerinin Harmonizasyonu Prosedürü. 22.09.2020. https://dosyamerkez.saglik.gov.tr/Eklenti/15143/0/karar-siniri-esik-deger-kriek42009846pdf.pdf (accessed October 2, 2026)
• T.C. Sağlık Bakanlığı. e-Nabız Kullanım Kılavuzu V2.1. 2025. https://enabiz.gov.tr/document/User_Manual.pdf (accessed October 2, 2026)
• Nieman LK et al. The Diagnosis of Cushing's Syndrome: An Endocrine Society Clinical Practice Guideline. J Clin Endocrinol Metab. 2008;93:1526-1540. https://doi.org/10.1210/jc.2008-0125 (accessed October 2, 2026)
• Fleseriu M et al. Consensus on diagnosis and management of Cushing's disease: a guideline update (Pituitary Society). Lancet Diabetes Endocrinol. 2021;9:847-875. https://doi.org/10.1016/S2213-8587(21)00235-7 (accessed October 2, 2026)
• Fassnacht M et al. European Society of Endocrinology clinical practice guidelines on the management of adrenal incidentalomas. Eur J Endocrinol. 2023;189:G1-G42. https://doi.org/10.1093/ejendo/lvad066 (accessed October 2, 2026)
• Clinical and Laboratory Standards Institute (CLSI). EP28-A3c: Defining, Establishing, and Verifying Reference Intervals in the Clinical Laboratory. 2010, reaffirmed in 2020. https://clsi.org/shop/standards/ep28/ (accessed October 2, 2026)