I received an e-mail from a lady who had already received a diagnosis of hypothyroidism and was being treated for it. She also suspected that she might be suffering from co-morbid (co-occurring) Adrenal Fatigue and related this to her Doctor. He ordered her a blood test of her blood cortisol level (major adrenal hormone) and she asked me if I thought this was a good test for Adrenal Fatigue or Adrenal Insufficiency. I expressed to her my opinion about blood testing needing to be the one called the "ACTH Stimulation Test", also called the "Cortrosyn Stimulation Test", which can rule out or confirm true Adrenal Insufficiency but I also pointed out that saliva testing done at multiple times during a 24 hour period, can also detect a low cortisol rhythm as well, such as that which manifests in adrenal fatigue. I mentioned to her that a single blood draw of cortisol levels is like a snapshot reading and doesn't establish how the cortisol rhythm is functioning throughout the day. Following was my e-mail response to her question.

E-MAIL RESPONSE:

A single blood draw, of cortisol, is like a snapshot reading, so doesn't really establish what your cortisol rhythm is doing. A better test of adrenal function is the "ACTH Stimulation Test", which takes a baseline reading then two more at thirty minute intervals, after giving the patient an injection of the ACTH hormone (the one that stimulates cortisol production). They want to see a significant increase in cortisol with the two stimulated readings and if there isn't an adequate increase, they may diagnose adrenal insufficiency.

There are also saliva cortisol tests available that establish your cortisol circadian rhythm because these test kits contain tubes to collect samples at 3 or 4 different times during a 24 hour period. These are not terribly expensive and a lot less expensive than an ACTH Stim Test but may not matter if you have insurance that covers all of your diagnostic tests. Many pharmacies carry the saliva ones, usually the "ZRT Labs, Inc." brand, so you might check with your local pharmacy. If they do not carry them, ZRT tests are available online, link>> http://www.salivatest.com/ .

The National Institutes of Health and the World Health Organization, recognize saliva cortisol testing as being very accurate. Major insurance providers also recognize saliva cortisol testing, including Blue Shield.

Here are a few links, two being from the National Institutes of Health "PubMed' website and the other from the endocrine society that state clearly, the accuracy and convenience of saliva cortisol testing:

PubMed; "Salivary cortisol--an alternative to serum cortisol determinations..."
www.ncbi.nlm.nih.gov/pubmed/9638346

PubMed; "Salivary cortisol measurement is inexpensive and noninvasive and offers many advantages over serum testing."
www.ncbi.nlm.nih.gov/sites/entrez?db=pubmed& uid=9752108&cmd=showdetailview&indexed=google