Most literature will mention three kinds of “adrenal insufficiency”.  Any of these can result in having too-low levels of the steroid cortisol. Some patients might even see low levels of another steroid released by the adrenals–aldosterone. But low cortisol is the most common result.

Some patients can find themselves with low blood sugar, as well, aka hypoglycemia. Why? Because cortisol is needed to get blood sugar to the cells.

Lets look at the three most-often mentioned kinds of “adrenal insufficiency”

  1. PRIMARY – This is a form that fits the disease called Addison’s, meaning the adrenal glands have a problem within themselves.  Primary can also fit someone with a rare situation of having damaged adrenals, or even more rare, adrenal glands removal. Doctors will be looking for a low serum cortisol result, but can also check for a high plasma ACTH test result for Addison’s disease (but not while a patient is on cortisol supplementation). Testing for Addison’s can include the ACTH stim test1 or any overnight Metyrapone stimulation test.
  2. SECONDARY – This form fits someone who has a messaging problem like hypopituitary, since the adrenals work primarily from being messaged by the pituitary gland via the release of the ACTH hormone to tell the adrenals to produce cortisol.  So if ACTH becomes low in ‘production or release’ from the pituitary, cortisol can become poorly released by the adrenals. Doctors might use the plasma ACTH test to discern this situation, seeing if it’s low. Other ways to discern hypopit including finding oneself with both a low TSH and a low free T3 (when not on thyroid meds), or testing other messenger hormones like FSH (follicle stimulating hormone), LH (Luteinizing hormone), GH (growth hormone), etc.2
  3. TERTIARY – This rare situation refers to a problem coming from the hypothalamus. In other words, there is a feedback loop that starts with the tiny gland called the hypothalamus, which is meant to release a messenger hormone called the corticotropin-releasing hormone (CRH) to the pituitary, and the latter to release the messenger hormone ACTH towards the adrenals.

But there’s a 4th kind of low cortisol, which is more aptly called “hypocortisolism”– the most common which hypothyroid patients acquire!

This kind of low cortisol has nothing to do with the other three mentioned above, and is what Dr. Laura R. Stone, MD terms “hypocortisolism”, and has also been called “adrenal fatigue” over the years. The website and books related to Stop the Thyroid Madness observed this kind of low cortisol repeatedly right after the turn of the 21st century, (This can also happen to healthy people under chronic stress or who exercise too hard/too often)

4. HYPOCORTISOLISM/ADRENAL FATIGUE – This refers to either moderate or seriously low cortisol that happens to a certain body of hypothyroid patients who are either…

a) undiagnosed for awhile (due to the medical community’s inane use of the TSH lab test and it’s ridiculous “normal range”)
b) treated with T4-only medications like Synthroid, Levothyroxine, etc, which leave all-too-many patients with lingering hypothyroidism, or
c) those who might have T3 or Natural Desiccated Thyroid (NDT) as their treatment, but are kept on too low of a dose, either because of the doctor’s use of the TSH lab test, or the patient feeling good on lower doses, but not understanding that it’s about being optimal.

In other words, many thyroid patients in these above situations will first see cortisol go high as the body’s response to the stress from any of the above, then different adaptive measures by one’s body against the high cortisol will start forcing cortisol levels down at different times of the day. Some patients eventually find all times of the day down. The lower cortisol can be moderately low or seriously low. You can read all above it in the STTM II book via Dr. Stone’s chapter titled Hypocortisolism: An Evidence Based Review

How to test for #4

Patients over the years, as first reported by Stop the Thyroid Madness, have found saliva testing to be the best choice to test for this 4th version of adrenal insufficiency, not blood. Why? Saliva is measuring what is unbound and available for use (unlike blood testing, which is mostly measuring what is bound), and saliva testing measures at four key times during the day–the latter giving important information as to treatment. Here’s a page showing where results fall when a patient doesn’t have a cortisol problem….which you can compare to once your saliva results are back.  It’s NOT just about falling anywhere in the normal range, which most saliva test facilities do NOT get, nor do most doctors, .

What might be the wisest step a thyroid patient can do if they find themselves with low cortisol?

If there is any suspicion that one might have any of the first three versions of a cortisol problem, one can ask their doctor for the right testing for any of the first three (before getting on any cortisol-containing supplements like Adrenal Cortex or medications like Cortef/HC, which can suppress the ACTH)…just in case. Makes complete sense to find out, because #1-3 might mean HC for life, whereas with #4, patients have been able to successfully wean off HC or Adrenal Cortex AFTER they have corrected all issues which can stress the adrenals.

Also note that patients have reported over the years that they find it unwise and risky to treat totally by symptoms without doing testing, since some symptoms of high cortisol can be similar to some symptoms of low.

For #4, here’s a page of a succession of Discovery Steps to discern if one has a cortisol problem as a thyroid patient. Note that the 4th important step is saliva testing for #4. Also see Chapter 5 in the Updated Revision STTM book for more excellent information.

Finally for #4, patients have reported that the use of HC/Cortef is the last choice of treatment, usually only if the results are seriously low in the saliva result ranges and three or more times. Moderately low cortisol has found success with adrenal cortex supplements–both while discovering and correcting all the issues which led to the low cortisol in the first place.

Please note that the above is information, not a diagnosis. Please work with your doctor.

P.S. Some patients wonder if Lyme can be another cause of hypopituitary or a problem in the hypothalamus.


**For how to discern if one has the 4th kind of adrenal insufficiency, see this page.

**For some wisdom about #4, see this page.

**To interpret any lab result, see this page…because it’s NOT about just “falling in the normal range”

**To order the STTM books, go here.

**To find a good doctor to work with, and hopefully one you can guide with patient knowledge, go here.

**To read about Cushings Disease (high cortisol caused by a problem, not the same as mentioned above in response to stress and FAR more common), see the bottom part of this page here.

**For those who are gluttons for educational punishment, here’s an extremely detailed article on #1-3, and here. 🙂



Important note: STTM is an information-only site based on what many patients worldwide have reported in their treatment and wisdom over the years. This is not to be taken as personal medical advice, nor to replace a relationship with your doctor. By reading this information-only website, you take full responsibility for what you choose to do with this website's information or outcomes. See the Disclaimer and Terms of Use.