Toxic Plants: A Brief Historical Overview of Their Uses

Belladonna is one of the most toxic plants found in the Eastern Hemisphere.[17] All parts of the plant contain tropane alkaloids

All throughout history, toxic plants have been used as poisons and in other ways. Understanding history is the first step toward avoiding the danger today.

History is rich with stories of how people have used plants. Whether as healing herbs or poisonous potions, plants have played an important part in human affairs. They still play an important role, but they aren’t used as poisons as frequently because there are chemical and synthetic compounds that are easier to acquire and more effective. Some plants can still kill, though, as evidenced by their historical – and sometimes misguided – uses.

Toxic Plants in Ancient Rome

In Ancient Rome, mass poisonings and mass suicides regularly occurred during times of war and during epidemics. These started in the fourth century BC and continued all the way into the second century AD. Hemlock, nightshade, belladonna, mandrake, and opium were just a few of the plant poisons used by the Romans, both in suicides and murders. Hemlock mixed with honey was one of the most widely used poisons during that time.

Toxic Plants as a Beauty Regimen

Belladonna was especially popular with women because when they used it on their skin it made their cheeks red and their eyes bright. But belladonna is a deadly poison. Even in ancient times people knew this, and a tincture of belladonna leaves was a common poison used then. Despite the danger, women continued to use it for some time because they loved the way it made them look and it helped them attract men.

The Roman emperor, Claudius, was killed with a tincture of belladonna prepared by the infamous female poisoner, Locusta. The legend has it that his wife’s accomplice painted this on his throat with a feather when a dish of poisonous mushrooms failed to kill him. The Stoic philosopher and writer, Seneca, also drank a poison made from hemlock after Emperor Nero accused him of being involved in a conspiracy.

Based on historical research, it’s also quite likely that Cleopatra committed suicide by poisoning herself, rather than by clasping an asp to her breast. The most likely poison was belladonna, because it was convenient at the time and very easy to acquire.

Suicide, Royalty, and Conquerors: More Uses of Toxic Plants

Yew extract was another common plant poison used in ancient times, and the British King Catuvolcus committed suicide by using this extract. According to other legends, the Scots often killed their Danish conquerors by leaving them barrels of beer poisoned with the sap of the belladonna plant. They saw the beer as a gift or a peace offering and drank it readily, without thinking that it might have been poisoned. By the time they realized it, it was far too late to do anything about the poison they had ingested.

Because toxic plants were so popular throughout history, much has been written about them. They remain a fascinating and dangerous part of historical study and observation, and occasionally give insight into the present, as well.


  1. Bevan-Jones, Robert (2009). Poisonous Plants: A Cultural and Social History. Windgather Press.