How poison kill someone?

Poison can kill someone by interfering with essential biological processes in the body. Depending on the type of poison, it may disrupt cellular respiration, impede the function of vital organs, or cause irreversible damage to tissues. Some poisons can lead to rapid systemic failure, while others may cause gradual deterioration over time. Ultimately, the mechanism of action varies by poison, but all can result in fatal outcomes if not treated promptly.