Strange case (1 day remission) ...

Hi there.
Once, I got mushroom poisoning. I was vomiting and couldn’t get off the toilet all night. I started taking activated charcoal. It took me some time to recover.

But the most interesting thing was that my arthritis went into remission! I was able to walk without any pain. As soon as the poisoning symptoms went away, my joints started hurting again.

What could explain this? Did my immune system somehow switch modes?
(I have Psa for 7 years now. Never treated it. Only painkillers.)