I knew a house painter that would find a fire ant nest and bury his hand up to his wrist in it before he started painting. Claimed the fire ant venom relieved his arthritis in his hand.
Could be legit, insect venom can numb the nerves (like botox) so maybe he just didn’t feel the pain from the arthritis.
I think you would want to build up a tolerance to the venom before shoving the whole arm in though!