To stop the pain of a jellyfish sting, pour seawater over the affected area for ten minutes to deactivate any remaining
toxins. (Fresh water releases remaining toxins instead of deactivating them, increasing the pain.) Then, soak the affected area in vinegar. Then apply ice.
If vinegar is not available, apply baking soda, rubbing alcohol, meat tenderizer, or diluted ammonia.
The old-fashioned cure for a jellyfish sting is one's own urine since it contains plenty of ammonia.