Beating
It is speculated that he was beaten and left in a delirious state with a high fever.
This could be from after “injuring” a woman, whether emotionally or physically, a ruffian set out to make Poe pay for what he did. By beating the sense out of Edgar Allen Poe
Or it could be that after getting extremely drunk with some friends Poe was beaten and robbed by ruffians, and left to die.
Rabies
This theory t
Carbon Monoxide poisoning
Heavy Metal poisoning
Alcohol
Brain Tumor
Flu
Murder
Cooping