Overnight 1mg Dexamethasone Suppression Test

The Overnight 1mg Dexamethasone Suppression Test is a diagnostic procedure used to assess cortisol production by administering 1mg of dexamethasone at night and measuring cortisol levels the next morning.

What to expect:

  • This test involves having baseline blood sample taken in first morning, taking 1mg of Dexamethasone tablets at night, and then having a second blood sample collected the next morning.

Note: If you have any significant allergies, especially to steroids, please consult with your doctor before returning for the test.

Your Appointment for Dexamethasone Suppression Test

Day 1 appointment

  • No preparation or fasting required.
  • A blood sample will be collected between 8am and 9am
  • 1mg of Dexamethasone is supplied by QML Pathology. This is packaged as two 0.5 mg tablets. Please take the two tablets at 11pm on day one.

Day 2 appointment

  • Return to the Collection Centre between 8am and 9am to have a second blood sample collected.
  • This completes the test.
Overnight 1mg Dexamethasone Suppression Test
Pre-test collection information

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