What is the worst kind of pain anyone can go through?

I'd go with the pancreatitis that I had. Perfect 10. The only way to track it then was to not give you pain meds until you were out of the woods, or you might die. I forget from what exactly. The length of time this takes I gathered varied. In my case it was caused by a virus. I loved the pain meds when I finally got them. Ah sleep.

The worst kind of pain is to watch someone you love, suffer towards the very end of their life. My grandfather suffered from a motor neuron disease, which was diagnosed seven years prior to passing away. During the seven years, he lost function of his left hand, then arm, leg, until eventually he had a cardiac attack and half his body(the left side) was in utter paralysis. He was completely dependant on others for even the smallest tasks. Can you imagine having to ask someone to comb your hair, feed you, scratch your back during an itch and to change bedpans? Can you imagine having to ask it and not be fully understood, because the functioning of your voicebox is also impaired? Towards the end, he couldn't eat and a pipe had to be put in to directly feed food in. Can you imagine all that happening to a person who loved life more than anything. And his hoping for a quick death so he could spare his family the pain of watching him? You can be the biggest person in the world, but when you can't save a loved one- somebody who you'd give your life for, there's no bigger pain in the world.

Worst immediate - it would be a toss up between dental, childbirth labour and multiple broken bones would be my best guess. Which one is worst may also depend from person to person - not sure if there is a specific study that has been able to capture which of these may be the most painful. It's difficult to weigh up if one of these are more painful than the loss of a loved one by death, departure or distance! Just theoretically speaking if I ask myself would I agree to enduring dental, childbirth labour or broken bones if that was the only way I could stop the loss of a loved one...the instinctive answer may be "yes". But I can't be sure how honest that answer really is till someone really does pose that question! And maybe I don't want to find out which is the worst kind of pain one can go through! It's terrible enough having to go through any of these at all.

Living longer than your own child. Even worse would be if there is no sensible reason for it. One could come to accept it if the child died in an act of heroism of some sort, it would still be painful, but the pain could be dulled by a sense of pride. Without anything like that or anything to blame would be too much for most people.

Renal colic (when a renal stone is passing down the ureter from kidney to bladder) is a diagnosis you can make from the end of the street because of the screaming. The pain is overwhelmingly intense and then suddenly switches off when the stone pops out into the bladder. Personally - the most intense pain I have ever experienced was when I volunteered for a neurophysiology experiment for a friend. He was examining the effect of low oxygen tension on peripheral nerve function. As the experiment proceeded we arrived at a point where only the pain conducting fibres were still functioning and when he applied a very modest painful stimulus I experienced pain of an intensity that I would not wish to repeat.

Loosing both or all your children at the same time.  Sheer, unremitting agony.

Just to expand the discussion beyond physical pain and emotional pain of loss, what about spiritual pain? I see two forms: Missing Life's Purpose The pain of not knowing why we are here and what life is for, and having no physical (including direct mental) connection to one's maker. This might not be a pain at all for some who enjoy the ability not to think about it. But for some of those that must think about it, no greater spiritual pain may exist. Regret I imagine a rapist or a child abuser who comes to understand his or her mistake and for the rest of existence (which may be much longer than life on Earth) must experience the pain of sadness and regret in not having lived a life free of evil desires and tendencies. If it is how the Christians put it that "the meek shall inherit the Earth" or that the (innocent) children will most easily enter kingdom of God, then for the rest of us that have eaten from the Tree Of The Knowledge Of Good And Evil, we will all carry the pain of our mistakes, some of which might be so great that it completely alters the path of our evolution. The pain of not having walked (lived) a clean or cleaner evolution, along with the knowledge that the past cannot be undone might just be the greatest pain possible.

I have heard it argued that thirst is the worst way to die.  It makes sense.  Sheer, constant, unremitting agony that is not short-lived, as everything is focused on finding water.  The lore is that it drives one crazy.

Emotional pain: loosing a child Physical pain : child birth, kidney stones, gout