Cortisol Awakening Response (CAR) Profile – Advanced Assessment of the Body’s Stress Response

The Cortisol Awakening Response (CAR) Profile from ZRT Laboratory provides a detailed evaluation of adrenal function and the hypothalamic-pituitary-adrenal (HPA) axis, helping uncover how effectively your body adapts to daily stress.

This non-invasive saliva test measures six cortisol samples throughout the day—three within the first hour after waking and three taken later in the day—along with a single DHEA-S measurement. By observing cortisol changes immediately after waking, this profile reveals whether your stress response is healthy, blunted, or elevated, offering valuable insight into adrenal resilience and overall well-being.

▶ Watch Video Overview

Why the Cortisol Awakening Response Matters

Cortisol, often called the “stress hormone,” follows a predictable daily rhythm. In healthy individuals, cortisol rises sharply—up to 50%—within 30 minutes of waking, then gradually declines throughout the day. This Cortisol Awakening Response (CAR) reflects how your adrenal glands and brain coordinate to handle physical, mental, and emotional stress.

A balanced CAR supports energy, motivation, and emotional stability. A blunted or exaggerated CAR may be associated with conditions such as:

• Chronic stress or burnout

• Fatigue and low stamina

• Depression, anxiety, or PTSD

• Sleep disturbances or insomnia

• Chronic pain or immune dysfunction

What This Test Measures

Six salivary cortisol measurements over 24 hours provide a comprehensive view of daily hormone rhythm:

• Immediately upon waking

• 30 minutes after waking

• 60 minutes after waking

• Before lunch

• Before dinner

• At bedtime

A single DHEA-S measurement is also included to evaluate adrenal reserve and balance between cortisol and DHEA—two key hormones that regulate stress adaptation and recovery.

WHY CHOOSE THIS TEST

The Cortisol Awakening Response Profile helps pinpoint subtle adrenal imbalances that may contribute to fatigue, irritability, brain fog, sleep problems, or chronic stress. By understanding your specific cortisol rhythm, your healthcare provider can design a personalized plan to restore healthy HPA axis function through lifestyle changes, nutritional support, or adaptogenic therapy.

Ideal For Individuals Experiencing:

• Fatigue or burnout

• Anxiety or morning nervousness

• Difficulty waking or low morning energy

• Sleep disruption or insomnia

• Mood swings or sugar cravings

• Frequent illness or poor stress tolerance

TEST REQUIREMENTS

This non-invasive test requires six timed saliva samples collected throughout the day using the easy, at-home kit. Samples are stable for mailing and do not require refrigeration.

INCLUDES

✅ Cortisol Awakening Response (CAR) Profile
✅ Doctor’s Review and Interpretation of Results
✅ Personalized Recommendations for Stress and Adrenal Health

Important: This test is not available to residents of New York State. Orders or samples originating from New York will be canceled, and any specimens received will be discarded.