And now for something completely different

Perigren. That's what it's called. The drug that destroyed the world. It's just a little pill. Who could have imagined that a little white pill, no bigger than a penny, could end the word? Yet, it happened. The world is over. Governments are gone, chaos reigns, and the only currency left is force. In this world, the strong survive. Well, the strong and the guys with the Perigren, anyway. I am Gil Handersen, and I might be the last sane man left.
Perigren. It started as a military experiment, something to give to soldiers with fatal wounds. Something that would allow them to defy death long enough to win the fight. The scientists got it figured out. I don't know how, but they did it. One little pill and it would become impossible to die for two weeks. In fact, the only way to kill someone on Peregrin is to destroy their brain. Almost like zombies, except these are still humans. Humans who have sold their lives for this power. The pills were quickly rushed into production, without even testing. The pills worked, though. Massive blood loss could be ignored while on Peregrin, burns were inconsequential. In fact, it was discovered that while on Peregrin, it was unnecessary to sleep, eat, drink, or do basically anything that was previously considered necessary. That's the story of the origin of Peregrin. Now it's time for the story of how it destroyed the world.