Diurnal Cortisol

Test Details

Lab Company: ZRT Laboratory
Sample Type: Saliva
Collection Location:  At Home

The Diurnal Cortisol test measures cortisol levels throughout a single day. It helps assess adrenal hormones and adrenal gland function.    

🔑 Key Details 📦 Shipping
Preparation & Timing 📊 Results
🧪 Collection Instructions 📚 More Resources
💳 Requisition & Payment
💬 Questions?

Key Details 

  • You can collect your samples any day of the month if you are not taking hormones.
  • If you are taking hormones, you may need to collect your sample at a specific time. 
  • Avoid anti-aging/anti-wrinkle facial creams for at least 3 days prior to collection. 
  • Do not eat, drink anything but water, or brush your teeth for at least 2 hours prior to collection.
  • Collect your first saliva sample upon waking.
  • Freeze your sample if not shipping within 24 hours of collection.

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Preparation & Timing

  • You can collect your samples any day of the month if you are not taking hormones.
  • If you are taking topical or oral hormones, 
    • Avoid applying topical hormones with your bare hands for at least two days prior to collection (use latex gloves, an applicator, or a hormone-loaded syringe).
    • Take/apply any night dosage at least 12 hours before your planned morning collection. 
    • Avoid using hormones on the face, lips, and neck.
    • Change sheets, pillowcases, and hand towels the night before collection.
    • Avoid touching any surfaces which may be contaminated with hormones.
  • If you are taking hormone patches, vaginal rings, hormone pellets, or hormone injectables, test halfway between doses. 
    • For example, 3 days after a once-a-week patch.
  • Do NOT take this test if you are taking hormone troches or sublingual therapies.
  • If you are taking steroids, talk to your healthcare practitioner about proper timing.
  • For 3 days prior to collection, 
    • Avoid taking 7-Keto DHEA.
    • Avoid anti-aging/anti-wrinkle facial creams.
  • Do not eat, drink anything but water, or brush your teeth for at least 2 hours prior to collection.
  • Collect your first saliva sample upon waking.

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Collection Instructions

  1. Collect your saliva sample within 30 minutes of waking for the day.
    1. Use the large tube.
  2. Wash your hands with soap and water.
  3. Use a clean towel to dry your hands.
  4. Rinse your mouth with water.
  5. Wait 5 minutes before beginning collection.
  6. Allow saliva to pool in your mouth and then transfer it to the tube. 
    1. Smelling food, yawning, or pressing the tip of your tongue against your teeth can help with saliva flow. 
  7. Fill the tube at least half full, not including bubbles. 
    1. Collection typically takes 15-30 minutes.
  8. When finished, cap the tube.
  9. Write your name and the date and time of collection on the tube. 
  10. Place the tube back into the bag.
  11. Repeat steps 2-10 using the small tubes for each of the other three collections. 
    1. Collection 2: before lunch
    2. Collection 3: before dinner
    3. Collection 4: before bed
    4. Do not eat, drink anything but water, or brush your teeth for at least 2 hours prior to each collection.
  12. Place the sample tubes and completed test requisition form into the test kit box.
  13. Place the test kit box inside the provided, prepaid return envelope.
  14. *NOTE* If you make a mistake collecting your sample, rinse the collection tube out with hot water and no soap, shake out the remaining water, and let air dry. Re-collect at the appropriate time the next day. 

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Requisition & Payment

  • Your kit has been prepaid. You DO NOT need to pay anything extra.
  • Instructions on how to fill out your requisition can be found HERE.
    • Since you pre-paid for your tests, you do not need to fill in the payment information on any of these forms.

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  • Freeze your samples if you are not shipping within 24 hours of collection.
  • To prepare your samples for shipping,
    • Place the sample tubes into the bag.
    • Place the sample tube bag and the completed test requisition form back into the test kit box.
    • Place the test kit box into the provided, prepaid return envelope.
    • Affix the prepaid label or postage.
  • Make a note of your return tracking number so that you can track your sample back to the lab. 

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  • Results should be released to your provider 3-5 business days after samples are received at the lab. We cannot guarantee processing time. 
  • Your provider will notify you when your results are in and schedule a follow-up appointment for you to review them together. 
  • Your provider may choose to release your results to you. Rupa cannot release your results without provider authorization.

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More Resources

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For general questions, email Rupa Health at support@rupahealth.com. For test-specific questions, contact ZRT Laboratories by calling 866-600-1636 or emailing customer service at info@zrtlab.com