I’m helping to direct a young actor playing Hamlet and we’re going over the “O That This Too Too Solid Flesh” speech. Going over the text, it occurred to me: what happened to Hamlet’s father?
Shakespeare makes it clear that Claudius poisoned Hamlet’s father with a vial of poison that he put in the king’s ear:
Sleeping within my orchard,
My custom always of the afternoon,
Upon my secure hour thy uncle stole,
With juice of cursed hebona in a vial,
And in the porches of my ears did pour
The leperous distilment; whose effect
Holds such an enmity with blood of man
That swift as quicksilver it courses through
The natural gates and alleys of the body. Hamlet, Act I, Scene v, lines 796-805.
The Ghost calls the poison “cursed hebannon,” which fis a poison that Shakespeare made up. Interestingly, Shakespeare’s original source for Hamlet makes no reference to poisoning, but that the king was stabbed in front of his own court. I think Shakespeare might have changed this simply because Queen Elizabeth was concerned about assassination herself, and Shakespeare didn’t want to make it look like he approved of assassination. Then again, maybe he changed it so that the murder didn’t seem like a repeat of Julius Caesar, (which Shakespeare’s company performed the year before Hamlet, (Source: New York Times, 1982).
The Ghost describes how, when the poison went through his ear canal, he experienced violent swelling, sores, and unimaginable pain. He actually compares himself to Lazarus, Jesus’ friend in the Bible who died of leprosy.
And with a sudden vigour it doth posset
And curd, like eager droppings into milk,
The thin and wholesome blood. So did it mine;
And a most instant tetter bark’d about,
Most lazar-like, with vile and loathsome crust
All my smooth body. Hamlet, Act I, Scene v, lines 807-811.
Sadly, Leprosy is still prevalent in third world countries so its symptoms are still very well understood: CONTENT WARNING: DISTURBING IMAGES IN THIS VIDEO
The poison is made up, but could such a poison actually exist? I found a wonderful article from the Journal of ENT (Ear, Nose, and Throat), where the author John Riddington Young posits the kinds of real-world poisons that might have this horrific effect on Hamlet’s father.
What actual poison was used? Shakespeare states, “the juice of cursed Hebenon”  but sadly, there is no such drug. Did he mean hemlock, or perhaps henbane? Laurence Olivier actually substitutes the name hemlock in his 1948 film. Belladonna, aconite and nicotine have all been suggested, but the most likely culprit is taxine from the yew tree. It is a deadly poison and its Old English name was heben. Shakespeare would certainly have known of it; he says in Richard II, archers bend ‘their bows of doubly fatal Eugh’  (implying that apart from the arrows killing foes, there is an intrinsic toxicity in the wood).JOHN RIDDINGTON YOUNG:
“History of ENT – Murder most foul, strange and unnatural”
I found a case study of a real case of Yew poisoning that emphasizes that it is incredibly fast-acting, “Fast as quicksilver”, that it can be misdiagnosed as another poison (like a snake bite, as Claudius later claims), and that it has no known antidote, the perfect way to kill a king:
. The taxine alkaloids (for example, taxine A, 2-deacetyltaxine A, isotaxine B, 1-deoxytaxine B) derived from p-dimethylaminohydroxycinnamic acid are the effective poisons of the yew . In chemical terms, the compound is structurally related to veratrine, and the presence of an unsaturated lactone group makes this group of alkaloids similar to digitalis. Poisoning with the latter may be falsely diagnosed during a toxicological examination. Cardiac disturbances after intoxication by yew are ascribed mainly to the alkaloids paclitaxel and taxine B, affecting sodium/calcium permeability in cells . The taxine alkaloid is absorbed through the digestive tract very rapidly, and the signs of poisoning manifest themselves after 30 to 90 minutes. An infusion made from 50 to 100g of needles is considered to be fatal [3–5], as no antidote is known.Vališ, M., Kočí, J., Tuček, D. et al. Common yew intoxication: a case report. J Med Case Reports 8, 4 (2014). https://doi.org/10.1186/1752-1947-8-4
So if you are playing Hamlet, in addition to the sadness and anger you feel after losing your father, you could also feel revulsion and pity at the painful, disgusting and cowardly way he was murdered. Truly, “MOST FOUL STRANGE AND MOST UNNATURAL.”