I think caffeine is a personal thing.
I myself can't tolerate much very well, I have a tremor, and I can't even attempt handwriting, (or typing ) for that matter if I'd had too much caffeine.
Green Tea is great, It's low in caffeine.
And, it does have antioxidants.

But, too much, and I'm reaching for valium or topomax at least.

Oh of course they put caffeine in certain medications.
For instance fiorinal and fiorocet. Where the caffeine works on the vascular system in the case of a headache.

If you have a caffeine "habit", then you'll hafto adapt to life without it.
and, visa versa.

I became an expert on Migraine.. A guy I knew, ,called me and said Pete, I got this headache that has me sick, and I can't take it, any suggestions?
This guy and his wife had pots of coffee all day long. I asked him, you didn't have your full dose of coffee today did you?
He thought about it, and said I don't think so....
Go have a big cup.

He called me back an hour or so later.
The Migraine was Gone!

And, there are times when caffeine will Give me a migraine!

Go figure...

As for rsd, if you're not used to it, it can "tighten" muscles... but it's all what you're used to. imho.

Pete
asb