High dose steroids would wear off into the evening and night.
Cortisol is after all a fluctuating hormone with highs and lows in 12 hr cycles, with the lowest at 4am or so.

High dose steroids also raise blood sugars, and when those drop, it would be a big LOW blood sugar and give symptoms of that.
This could be a problem for those with impaired glucose utilization to begin with. It is something to consider.

I didn't have any of those issues, however.

Good point Mrs. D.

I highest steroid dose I was on was when I went to into Addisonian crisis for a stomach bug about 4 years ago. I had to get IV steroids put into my body until the bug started to pass in the hospital-but they played it safer rather than sorry, and gave me way too much (not that I don't appreciate the safer than sorry tactic-it is definitely preferable to me getting LESS steroids than I need during an infection like that)-it caused me to bloat, and my blood sugar went up considerably. It went back to normal as soon as I was down to my normal dose, though. Perhaps a blood sugar swing aggravated things.

What infections could last this long? My only thought would be Lyme but i've already tested negative. Cytomegalovirus?

No I wasn't really anxious. Maybe a little bit the first day, but that day I felt fine. It wasn't until the second day towards the evening it started.

You can have an infectious arthritis simmering, a sinus infection, a chronic prostatitis, even a simmering endocarditis. Many of these may come from infected teeth, tooth extractions, any staph intrusion. Some people have simmering viruses in the liver, but liver blood tests would show those. Simmering Herpes simplex and Herpes zoster, and Parvo virus. My son had a mono infection (he just felt terrible and tired), for weeks before I sent him to our doctor...(when he came home from college one year) and when she did his blood work his liver enzymes were sky high. He had to wait months for his wisdom tooth extractions because of it.

Do you have any weakness with your neuropathy? I ask because steroids can exacerbate symptoms in multifocal motor neuropathy (MMN). I wonder if it is possible to exacerbate other types of neuropathy as well...in rare cases. There are many drugs that cause opposite of target effect in some patients. I wouldn't rule out that this is the way you react to steroids...at least high dose steroids.

Have you considered trying a lower dose to see if the same thing happens? 80 mg, is a really hefty dose...much higher then most tapers!! You might cut in half and try 40mg.

I agree with Enbloc - a short course of steroids could be the best way for you to clarify whether your neuropathic pain is part of the inflammatory process. This is nagging away at you and I can't see that a short course would do much harm although I avoid them like the plague as they make me go bio polar.

To shock you a little about the CRP. Mine is usually in the low teens while my ESR is usually quite high - between 30 and 60. Over the last five weeks my CRP has risen up to 160 twice and gone down in between to as low as 6.7! The huge surges have corresponded with symptoms that have led to two week long hospital stays and were assumed to be because of infection the first time but second time - this time last week I was re-admitted - two hospital consultants, one a nephrologist the other general - found no sign of infection. My ESR has been steadily rising and is now at 78. Conclusion - this a reflection of out of control inflammation as part of the autoimmune disease process.

I am not taking steroids yet and not on NSAIDs because of stomach issues. Nothing is simple or straightforward in my world but if I had your issues I'd take steroids and use them to play detective.

I have read that intermittent fasting lowers crp. I've been doing it for about 4 weeks and feel pretty good. The first week is hard. I do the 16/8 method.

I don't have any noticeable weakness. When I had oral surgery, I was given IV dexamethasone which is another corticosteroid. My symptoms began a week later. Could it be a rare allergic reaction to steroids? It seems my body does not tolerate them well. At this point I don't think a lower dose will do me any good. I just hope this eventually resolves over time.

If you had a reaction last time you received steroids in a different form & route, then YES, I would say an odd allergic reaction is possible. And it sounds like the results was even similar... you experienced the initial onset the first time, and increased symptoms of same the next time. Very strange. I wonder if this is the root cause to your symptoms.