One of Shakespeare's most famous love potions is used by the fairy Puck in A Midsummer Night’s Dream, and made from a flower called ‘love-in-idleness’, otherwise known as the wild pansy (Viola tricola).
The potion is created when Cupid shoots an arrow at 'the imperial votaress' (Queen Elizabeth I), but misses and instead hits the flower. The petals turn from white to purple, and the flower's juice becomes a love potion. Puck then places the potion on the sleeping eyes of Lysander, and later Demetrius which causes chaos in the forest.
In the natural world, petal colour is an important feature of plants, as insects use petal designs to determine where they should land to collect nectar. Many insects can also see a broader spectrum of light than humans including ultraviolet, which means that flowers look significantly different in 'insect view'.
Scientifically speaking, viola tricolor is not able to induce love, but extracts from the plant have been shown to be anti-microbial and cytotoxic. Cytotoxic chemicals can kill whole cells so may be able to treat diseases caused by uncontrolled growth, like cancers.
There does however exist a 'love hormone' known as oxytocin which can foster feelings of love or affection in humans, and the hormone dopamine which is released when we kiss, has been found to stimulate the same areas of the brain as heroin and cocaine.
Photo credits
Viola tricolor; creative commons on Flickr Jose Luis Cernadas Iglesias
Bee on pansy; creative commons on Flickr Orangeaurochs
In the final act of Romeo and Juliet, our tragic heroine takes a potion to fake her own death and place her into a catatonic state. Many believe the potion is most likely to be deadly nightshade (Atropa Belladonna) a plant native to Europe.
Other soporific candidates that are found in nature could have been the seeds of the bulrush plant, or a herb called leopards bane. Both of these plants are toxic, however none would have the capacity to induce a coma with a heartbeat so slow it could be mistaken for death.
Upon finding Juliet and believing her to be dead, Romeo uses a powerful, fast-acting poison to take his own life. An obvious choice for such a strong poison is potassium cyanide or the medieval monkshood, both of which cause rapid respiratory failure.
First Image Credit: Romeo gives money to an apothecary for a potion that will fake his death. First published by Bowles and Carver, courtesy of Wellcome Images, London.
Second Image: Atropa Belladonna. Danny S. 2008.
In Antony and Cleopatra Act 5 Scene 2 Cleopatra, on learning of Mark Antony's death and being unwilling to be taken alive by Caesar, sets in motion her own suicide by an asp bite to the breast.
A late 19th century painting of Act IV, Scene 15: Cleopatra holds Antony as he dies.
In ancient history, an asp referred to a number of different venomous snakes from around the Nile region. Cleopatra had already administered the venom to criminals to test its effects and believed an asp bite allowed for a much more humane death.
There are four main types of snake venom; proteolytic, which disrupts the molecular structure of the bite region, haemotoxic which affects the blood and cardiovascular system, neurotoxic which acts on the nervous system and cytotoxic which has a localised effect at the bite site.
The asp venom that was most likely used by Cleopatra is both neurotoxic and cytotoxic and would have caused a particularly excruciating death. The venom first stops signals to the muscles, and later to the heart and lungs. Victims die from respiratory failure.