Cortisol testing

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Saliva cortisol testing
• Provides four measures to show diurnal curve
• Done at home
• Measures free (unbound) cortisol
How to order and complete
• Order a ZRT Labs 4x saliva cortisol kit
• Stop meds/supplements affecting cortisol or HPA axis for two weeks
• Use normal waking and bedtimes*
• Do not exercise day prior to or day of test
• Freeze each sample as it is done
• Overnight kit late in the day Monday to Thursday for weekday
morning delivery
Note: The lab says the samples are stable for two weeks, but we believe the
most accurate results are obtained when the samples are frozen and the kit is
*Someone who has an unusual sleep schedule for an extended period of
months or years may need to use his or her normal wake up time and bedtime
for the first and fourth samples. The second sample is then collected four to five
hours after the first, and the third sample four to five hours after the second.
The standardized times identified in the kit would be disregarded.
Results overview
Example 1
Optimal levels
• Morning at the top of the range
• Noon approximately 75% of the range
• Evening close to 50% of the range
• Nighttime at the bottom of the range
Example 2
Morning and noon low (not less than 50% of range); nighttime and
possibly evening high
• High nighttime level is direct result of low daytime levels
• Adrenals try to catch up production
• Correct low daytime levels to correct high nighttime
• Correct with less intensive support than hydrocortisone
Example 3
Morning less than 50% of range; all other levels low
• No evidence adrenals can catch up production
• Usually requires a physiologic replacement dose of hydrocortisone
Example 4
Morning high over range; all other levels below range
• Incipient crash or adrenal crisis
• Requires a physiologic replacement dose of hydrocortisone
Example 5
Morning at bottom or below range; other levels at or below range at
most times; nighttime may be above range
• Seek diagnosis of adrenal insufficiency from qualified physician
Example 6
High levels at most or at all times
• Frequently a precursor to low levels
• From stress, internal and/or external
• Can be caused by systemic conditions such as
• long-term hypothyroid
• high glucose
• gastrointestinal issues
24-hour cortisol urine test
• Measures the amount of unbound cortisol excreted in 24 hours
• Cannot show diurnal variation
ACTH stimulation test
• Used to diagnosis primary adrenal insufficiency or pituitary issues
• Only indicates whether adrenals are capable of producing cortisol
• Does not reflect availability of free cortisol