But did he (Seung-Hui Cho) go on his rampage because he was taking the meds or because he quit taking them? - Bee-dubya-ell

That's a good question, but no one can answer it. Cho's medical records went missing. That shooting (Virginia Tech) was one of the more muddied ones. It took place in an area that's in the heart of the U.S. intelligence community, and his folks both had long-time government connections. But from what people have been able to piece together, he most likely quit taking his meds and was going through withdrawal.

One of the worst things you can do with these drugs is quit taking them cold turkey.