What exactly are greenies? I know they are a form of speed, but are they on par with crystal meth? It’s good

that baseball has finally banned this substance. All we need is a bunch of meth addict players running around. Not really sure how they can take a few greenies and then play baseball. I would think it would make their blood pressure high, etc, higher risk for heart attack, stroke, diabetes. It’s a good thing baseball finally banned them. you agree?