[parkovski]

I'm not an expert on any of this, medicine is just a hobby of mine. I don't think actual Parkinson's is caused by drug abuse though, I think it's a separate disease (or maybe more than one) that ends up doing the same type of damage to the brain so the symptoms look similar. Wikipedia seems to agree, we're not sure how most people affected got it. That seems to be kind of a theme in medicine.

As far as caffeine goes, I don't think it affects dopamine that much, so it probably wouldn't have that effect on its own. I can't imagine long term heavy caffeine use would be good for you though, I just don't think it would be enough to do the same damage that drugs that directly release dopamine do. Or at least, it would do different kinds of damage - my guess is memory issues due to lack of quality sleep and high blood pressure.