I had heard about Adolph's Meat Tenderizer as an antidote to the jellyfish sting, but have never tried it. Hopefully, I won't be at the beach when the jellyfish begin their journey to the beach.
xs, there's an old Friends' show where one of the girls get stung by a jellyfish, and one of the guys urinated on the sting to get rid of the pain. Urine has a lot of amonia in it. I haven't tried this method myself . . .
Poor xsboy. Nasty place to have been stung.