Testing for Cortisol levels during taper of prednisone

I asked this question at my last appointment. Rheumatologist said he wouldn’t order the test until I was off prednisone.

@lluth412
"I had a functional medicine person test cortisol this month - very high in the AM near non existent in the late afternoon."
-----------------------
That is "somewhat normal" for a cortisol level in the morning ---not completely normal in the afternoon.

When did you take your Prednisone dose? For a valid a.m. cortisol level test you can't take any Prednisone for at least 24 hours. Ideally, for a more accurate a.m. cortisol level when on a low dose of Prednisone --- you would need to hold your Prednisone dose for 48 hours.

It is debatable what the low dose of prednisone is. My endocrinologist said I needed to be able to maintain a 3 mg dose for an extended period of time before a morning cortisol level was warranted. I also needed to be "symptomatic" of adrenal insufficiency to warrant a cortisol level to be checked.

I must have been symptomatic enough to get my cortisol level checked and it was "quite low." However, my endocrinologist was somewhat surprised that I had a cortisol level so soon after being on moderately high doses of prednisone for 12 years. Since I had a cortisol level even though it was low ... my endocrinologist was "optimistic" that my adrenal function would continue to improve if I could stay on a lower dose of prednisone. She didn't want me to increase my dose any higher than 3 mg unless it was absolutely necessary.

The main point my endocrinologist was making was that my cortisol level wasn't ever going to improve unless I could stay on a very low dose of prednisone. I was reading that I shouldn't have any pain when treating PMR. My endocrinologist said I needed to expect "some pain" when trying to taper off prednisone. She said I shouldn't automatically increase my prednisone dose for "prednisone withdrawal pain" unless it was absolutely necessary. All the while, I needed to avoid things that could cause an adrenal crisis.

All of this is easier said than done!

@dadcue I wasn’t told anything about timing for the cortisol test. I did some research the day before and realized I should do an AM one so I could compare to the afternoon one. I fasted and didn’t do my prednisone dose or my inhaler before the test. But based on all the info above, neither test really told me much. I do have fatigue and it now looks like Hashimotos thyroid so we were trying to find all the things prednisone has done in my body so I can try to minimize the impact. Not easy!

And coming down on prednisone after so long is hard so trying to tease out “is this adrenal issues or withdrawal or asthma flare or am I just having a bad day?” is also not easy!!

@lluth412
"I had a functional medicine person test cortisol this month - very high in the AM near non existent in the late afternoon."
-----------------------
That is "somewhat normal" for a cortisol level in the morning ---not completely normal in the afternoon.

When did you take your Prednisone dose? For a valid a.m. cortisol level test you can't take any Prednisone for at least 24 hours. Ideally, for a more accurate a.m. cortisol level when on a low dose of Prednisone --- you would need to hold your Prednisone dose for 48 hours.

It is debatable what the low dose of prednisone is. My endocrinologist said I needed to be able to maintain a 3 mg dose for an extended period of time before a morning cortisol level was warranted. I also needed to be "symptomatic" of adrenal insufficiency to warrant a cortisol level to be checked.

I must have been symptomatic enough to get my cortisol level checked and it was "quite low." However, my endocrinologist was somewhat surprised that I had a cortisol level so soon after being on moderately high doses of prednisone for 12 years. Since I had a cortisol level even though it was low ... my endocrinologist was "optimistic" that my adrenal function would continue to improve if I could stay on a lower dose of prednisone. She didn't want me to increase my dose any higher than 3 mg unless it was absolutely necessary.

The main point my endocrinologist was making was that my cortisol level wasn't ever going to improve unless I could stay on a very low dose of prednisone. I was reading that I shouldn't have any pain when treating PMR. My endocrinologist said I needed to expect "some pain" when trying to taper off prednisone. She said I shouldn't automatically increase my prednisone dose for "prednisone withdrawal pain" unless it was absolutely necessary. All the while, I needed to avoid things that could cause an adrenal crisis.

All of this is easier said than done!

@dadcue
My endocrinologist said the life of prednisone is 18 hours so my fasting morning blood test should have been a true reading of my own cortisol level. Hope he was right. Was on 4 mg at the time of testing.

@caroljeand

It is probably okay for 18 hours but longer is better.

Specific Steroid Holding Times
Hydrocortisone: Hold for at least 24 hours before testing
Prednisone/prednisolone: Hold for at least 48-72 hours
Dexamethasone: Hold for at least 48-72 hours (preferred if testing must be done while on steroids as it has minimal cross-reactivity with cortisol assays)
https://www.droracle.ai/articles/267087/should-a-patient-take-oral-steroids-before-an-acth
---------------------
There might be other sources that say something different. Health care professionals are notorious for never agreeing on anything.

This is another reason why cortisol levels aren't done routinely. It might be difficult for PMR/GCA patients to hold their dose that long. I was able to hold my dose for 48 hours because Actemra prevented a PMR flare

@dadcue
I’m guessing I would have held off prednisone for 20 to 22 hours between my last dose and the blood test. So it probably told him what he needed to know. He determined my cortisol level was normal and felt I was producing cortisol. I tapered to 3 mg yesterday and feel ok so far. Maybe having had 4 kevzara injections has also helped.

@caroljeand

I would have never been able to taper off prednisone without Actemra.

I was on another forum and the experts said Actemra does nothing to the adrenals to promote recovery. I thought that was comical because one advantage of Actemra and Kevzara is that these biologics do nothing to the adrenals. They don't suppress adrenal function in the way Prednisone does.

You still need to taper off prednisone slowly because it takes time for adrenal recovery to happen. It doesn't happen like a light switch where the adrenals are either on or off. The adrenals don't suddenly "kick in" like some people say.

If you are lucky --Kevzara should make it easier to taper off Prednisone. It is about a 50/50 chance that you get completely off Prednisone. I think this is mostly due to how suppressed a person's adrenals get. My endocrinologist said I had resilient adrenals after I got off prednisone.

Good Luck with Kevzara!