@Fogbuster It would be wise to use current lab results for any kind of medical decision making. Your body may be doing something different than if did 2 years ago.
Tests that might be helpful are a 24 hour saliva or urine cortisol test, ACTH, an ACTH stim test. The 24 hour cortisol test eoujd tell you if you are making enough cortisol at 4 or 5 points during the day. A normal test eoujd look like this, with all points within range (the green area).
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Many of us have abnormal curves. Though some people have high cortisol, many of us find that ours is low at one or more points throughout the day.
Low cortisol can be dangerous and be part of a condition where the adrenal glands are not making adequate cortisol so the body cannot respond to stress, or even the demands of normal activity. At it's worst, it can provoke adrenal crisis, which can be life threatening, but many suffer from adrenal insuffiency, which can be a spectrum. Many doctors will only recognize full blown Addison's disease or adrenal crisis. This describes adrenal insufficiency and tests used to diagnose it.
https://www.niddk.nih.gov/health-in...enal-insufficiency-addisons-disease/diagnosis
In ME/CFS, it can be milder but still cause problems. The attached describes one doctor's thoughts on it, along with thee suggestion of replacing the inadequate cortisol production up to 15mg a day of hydrocortisone.
Dexamethasone us 20 times as strong as hydrocortisone. It is a powerful drug. It might be wise to familiarize yourself with the various steroids, their strengths and their purpose, how long they last, and the possible risks, benefits and side effects. If your body has the right amount, whether you're making it or taking it, you'll feel normal. Too little can cause negative symptoms, just as too much can.
My cortisol was very low 4 years ago. My doctor suggested hydrocortisone, and I was resistant, having heard negative things about steroids. But, my doctor convinced me to try it, and I went from being a sleepy heap in the floor to functioning. We found the right dose for me at the time was 25mg a day, taken in 3 doses - 10mg at 730am, 10 more at 11am and 5mg at 3pm. I had also failed an ACTH stim test, described in the link above, my level did not rise as much as a normal patient's.
Over time, as I solved other problems, I found I started to gain weight around my middle, and retested and found my cortisol was high midday. I was able to cut back on the dose, and take only 2.5-5mg once a day.
I did have an episode where I was given an IV drug which put an extraordinary load in my system, which threw me into adrenal crisis, with severe fatigue and excruciating pain above my kidneys. The doctor hadn't realized my adrenal function isn't normal still, but recognized my symptoms, and suggested I take dexamethasone, which resolved the pain from my adrenal glands within 20 minutes and I was able to take enough steroid to get me over the crisis then taper down to my normal dose of hydrocortisone.
Attention to this important area and appropriate testing and prescribing can really make a huge difference in symptoms and function.
One confusing area is the topic of "adrenal fatigue." When I was first sick, I read all I could in the internet and a couple of books on adrenal fatigue. I found it confusing as my cortisol hadn't been high - it was low - the "stages" of it didn't make sense, and I was doing all of the things recommended to "resolve" it but I was getting worse. The medical establishment isnt too helpful, saying there's no such thing, and only seeming to recognize full blown Addison's or adrenal crisis.
The reality is that many of the features of ME/CFS, whether infections, autoimmunity, toxicity if some sort, etc. all put stress on our bodies that our adrenals need to deal with. Holtorf's case, that many of us need to replace what we aren't making enough of makes sense. Too much can suppress out immune function, harm our bones, and cause unwanted weight gain. But, appropriately prescribed hydrocortisone or fludricortisone (fur those with low BP POTS) can be beneficial without the downsides.
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