[rjurney]

IANAD, but this sounds spot on. Nearly every problem he describes is explained by a slight adjustment to the pain threshold. His throat irritates him. His limbs hurt. He is tired. He can't focus. These are all things we all feel all the time. He feels them more.

It is consistent with responding to anti-depressants for a short time - before the initial semi-euphoric effects wear off, and then going off them once the trough after that begins. It is not uncommon for there to be a peak and a trough before stabilizing on an anti-depressant.

I wonder if OP has ever stuck with one anti-depressant for very long. They are very effective against this type of pain, whether the OP is depressed or not.