Topic: Banana skins
We first tried this on my sons verruca he had picked up from swimming.
I taped a small piece of banana skin (pith side down) on the verruca overnight and it had drawn the entire verruca out next morning leaving a hole in his heel about 5mm cubed.
I had a nasty splinter in a finger that was too painful to get out with a needle (wimp that i am) and did the same trick and next morning enough of the splinter popped out for me to get the tweezers on.
should work for drawing poisons out of wounds too, i think its down to enzymes in the banana skin having a powerful drawing action.