Detecting loss of normal diurnal cortisol rhythm: A hallmark of Cushing’s syndrome, where cortisol fails to decrease adequately in the evening. Use in the dexamethasone suppression test: After an evening dose of dexamethasone, evening cortisol is measured. Persistent elevation supports Cushing’s diagnosis. Assessing the full HPA axis: Useful for evaluating the hypothalamic-pituitary-adrenal axis when rhythm disorders are suspected. Monitoring effects of chronic stress: Severe chronic stress can alter normal cortisol patterns; evening measurement helps detect this impact.

Patients suspected of Cushing’s syndrome, especially those with elevated or borderline morning cortisol. Patients showing clinical signs of cortisol excess, such as central obesity, moon face, or high blood pressure. Patients with known pituitary or adrenal tumors. Occasionally, it is used to assess sleep disturbances related to chronic psychological stress.

Cushing’s syndrome symptoms: weight gain in the trunk, rounded face, muscle weakness, high blood pressure. Sleep difficulties (insomnia) associated with chronic anxiety or stress. Need for comprehensive medical evaluation of a suspected hormonal disorder.

Evening (4-6 PM): approximately 3-10 micrograms per deciliter (µg/dL). Midnight (10 PM - 12 AM): 50% of the morning value or > 1.8 µg/dL at night): indicates loss of normal physiological suppression, which is an important sign of Cushing’s syndrome.

Evening Cortisol (PM) Test | Lahalak Medical Platform

Analyze evening cortisol levels to monitor your daily hormonal balance, helping detect adrenal gland disorders and ensuring healthy sleep quality and proper physical relaxation patterns.

Scientific name: Evening Serum Cortisol Test (PM)

A quantitative test that measures cortisol hormone levels in blood serum, taken in the late afternoon or evening, usually between 4 and 6 PM (and up to 8 PM). The goal is to assess the normal decline phase in the daily cortisol rhythm. In healthy individuals, cortisol levels significantly decrease by evening. This measurement is often used in conju...

Evening Serum Cortisol Test (PM) - Evening Serum Cortisol Test

Service type Laboratory test (Blood)

Duration 10-15 minutes

Fasting Fasting is not required

Included Services

Cortisol (p.m) (Serum)
Consultation for results interpretation with an endocrinologist.
Personal support services from Lahalak

Medical Service Information

Purpose Test

Detecting loss of normal diurnal cortisol rhythm: A hallmark of Cushing’s syndrome, where cortisol fails to decrease adequately in the evening.
Use in the dexamethasone suppression test: After an evening dose of dexamethasone, evening cortisol is measured. Persistent elevation supports Cushing’s diagnosis.
Assessing the full HPA axis: Useful for evaluating the hypothalamic-pituitary-adrenal axis when rhythm disorders are suspected.
Monitoring effects of chronic stress: Severe chronic stress can alter normal cortisol patterns; evening measurement helps detect this impact.

Recommended groups

Patients suspected of Cushing’s syndrome, especially those with elevated or borderline morning cortisol.
Patients showing clinical signs of cortisol excess, such as central obesity, moon face, or high blood pressure.
Patients with known pituitary or adrenal tumors.
Occasionally, it is used to assess sleep disturbances related to chronic psychological stress.

Symptoms indicative

Cushing’s syndrome symptoms: weight gain in the trunk, rounded face, muscle weakness, high blood pressure.
Sleep difficulties (insomnia) associated with chronic anxiety or stress.
Need for comprehensive medical evaluation of a suspected hormonal disorder.

Frequently Asked Questions (FAQs)

What is the normal evening cortisol level? The normal range varies, but it is usually less than 50% of the morning value. More specifically, it is often below 3-7 micrograms per deciliter (µg/dL) or 83-193 nanomoles per liter (nmol/L) by 10 PM. A level above 1.8 µg/dL (50 nmol/L) at midnight is considered abnormal and indicates loss of normal suppression.
Why is this test requested along with the morning measurement? Diagnosis depends on the secretion pattern, not a single reading. In Cushing’s syndrome: Morning cortisol may be elevated or normal. Evening/night cortisol is abnormally high because it fails to decrease. Comparing the two readings reveals the disruption in the daily rhythm.
Can my sleep pattern affect this test result? Yes, significantly. If you work night shifts and sleep during the day, your daily cortisol rhythm is reversed. In this case, cortisol may be naturally high in your “evening” (your wake time). Therefore, it is very important to inform your doctor if you have an irregular sleep schedule. The sample should be taken at your personal “evening” time.

Normal Levels

Evening (4-6 PM): approximately 3-10 micrograms per deciliter (µg/dL).
Midnight (10 PM - 12 AM): < 1.8 micrograms per deciliter (µg/dL) or < 50 nanomoles per liter (nmol/L) is the important cutoff.
Normal (low) evening: indicates a healthy daily rhythm.
Elevated evening (>50% of the morning value or > 1.8 µg/dL at night): indicates loss of normal physiological suppression, which is an important sign of Cushing’s syndrome.

Conditions & Notices

• The timing of the sample is precise and critical. The sample must be drawn at the exact scheduled time by the physician (e.g., 4 PM, 6 PM, 11 PM). Accurate recording of the time on the tube is essential.
• The patient should be rested and calm for at least one hour before sample collection, as acute stress can elevate cortisol levels.
• The physician and laboratory should be informed of the patient’s usual sleep/wake schedule.
• They should be informed of all medications, especially steroids or psychiatric drugs.
• The sample is collected in a serum tube (red or yellow cap).