Modern anesthesia didn’t come into practice until around the mid-1800’s with the rediscovery of the properties of ether (Paracelsus had used it long before, but no one cared). Before ether came on the scene, people had to just “bite the bullet” and endure the pain of surgery, probably with some swigs of booze to take the edge off. In medieval England there were recipes for an anesthetic that were commonly circulated to “make a man sleep whilst men cut him.” The interesting thing about this drink, called Dwale, is that it was probably just as dangerous as surgery in pre-sanitation/antibiotic era medicine. Take a look at the recipe:
“How to make a drink that men call dwale to make a man sleep whilst men cut him: take three spoonfuls of the gall [bile] of a barrow swine [boar] for a man, and for a woman of a gilt [sow], three spoonfuls of hemlock juice, three spoonfuls of wild neep [bryony], three spoonfuls of lettuce, three spoonfuls of pape [opium], three spoonfuls of henbane, and three spoonfuls of eysyl [vinegar], and mix them all together and boil them a little and put them in a glass vessel well stopped and put thereof three spoonfuls into a potel of good wine and mix it well together.
When it is needed, let him that shall be cut sit against a good fire and make him drink thereof until he fall asleep and then you may safely cut him, and when you have done your cure and will have him awake, take vinegar and salt and wash well his temples and his cheekbones and he shall awake immediately.”
The bile was typically mixed with fat to help break up the ingredients and make them easier to absorb. Hemlock is the most recognizable ingredient on the list, and the most deadly (1 mL of hemlock juice can kill a person). It acts by blocking acetylcholine receptors in the nervous system, causing paralysis and blocking sensory impulses eventually causing respiratory failure. Bryony was used as a purgative in medieval England. Mandrake is also toxic. It acts like atropine, blocking muscarinic receptors. It also crosses the blood-brain barrier and induces sleepiness and hallucinations. The lettuce juice was thought to induce sleepiness. Opium obviously blocked pain. Henbane acts like mandrake, and induces a long period of unconsciousness. The vinegar, well, that woke the patient up (think smelling salts).
As you can see, there are some very dangerous ingredients. There’s speculation that dwale wasn’t as dangerous as it seems. The roots grown further north are often less potent than those grown closer to the equator (like in Greece, were hemlock killed Socrates). Boiling the ingredients also possibly detoxified them. Since the patient only had to drink enough until the passed out it’s not likely they ingested enough to poison themselves but we can’t know for sure.