Alexander the Great was what you might call a classic overachiever: He conquered the massive Persian Empire before the age of 30, but he was dead a few weeks before he would have turned 33. Although much of his life has been documented, exactly how Alexander died has been a matter of debate and speculation for more than 2,300 years. Some theories say he may have been felled by bacteria-laden water from the river Styx. Others say he may have contracted malaria, typhoid fever or West Nile virus, or died from the effects of a lifetime of alcoholism. But the most common theory states that Alexander may have been assassinated by poison-laced wine.

Now a new scientific paper backs up that theory. According to research published this month in the journal Clinical Toxicology, Alexander may have been poisoned by wine fermented from a plant called white hellebore, also known as Veratrum album. The paper's lead author is Leo Schep of the National Poisons Centre at the University of Otago in New Zealand, who first proposed this theory for a British television show back in 2003.

The new paper — co-authored with two other poisons experts and an expert in ancient literature — backs up Schep's initial theory with documentation that implies Alexander's inner circle conspired to assassinate him via poison. The researchers also examined reports of Alexander's symptoms during the 12 days he lay sick and dying — including abdominal pain, nausea, vomiting, bradycardia (low heart rate), hypotension and severe muscular weakness — and linked that to Veratrum album. In fact, they conclude that the plant was a more plausible poison than arsenic, strychnine or other botanicals that were in use during that era. The paper also links the nearly two weeks it took Alexander to die as another sign of hellebore poisoning.

So who would have administered the deadly dose? Schep told the Huffington Post that the most likely suspect would have been Alexander's cup bearer, who had the necessary access to the king. Other suspects linked to Alexander's death have included his generals, his illegitimate half-brother, or any of his wives, any of whom would have benefitted from his death.

Of course truly proving this poisoning theory would require something that nobody has access to: Alexander's body. The king's corpse has been lost to time, although it could still turn up one of these days. His father's body was possibly identified back in 2010.

Ironically enough, Veratrum album is today known not just for its poisonous qualities but also for a handful of minor medicinal uses. It is frequently sold as a homeopathic treatment for diarrhea and vomiting. Those uses, it should be noted, are not approved by the FDA.

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