system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How does a drug overdose kill you?

What happens in your body that might end up being lethal?
gpt
Depends on the drug. Heroin and other narcotics cause severe central nervous system depression which leads to respiratory failure (you stop breathing).

If it is something that causes stimulation to the sympathetic nervous system, like cocaine and meth, they can cause heart failure or even rhabdomyolysis, which is break down of muscles that is so severe that calcium and potassium will release into the bloodstream and cause the heart to go into ventricular fibrillation, which will result in cardiac arrest.

Over the counter drugs like ibuprofen and Tylenol, among many other drugs, are eliminated by your kidneys and liver. Too much causes severe damage to those organs and they shut down.