Unlike what you see on movies and television shows, urinating on jellyfish stings is not the recommend treatment. In fact, urinating upon the site can cause additional stings. Jellyfish stings can cause immediate pain and burning for several hours. Raised, red welts develop along the site of the sting, which may look as if you have been hit with a whip.
Avoid rubbing the affected area with your unprotected hands. The remaining tentacles can attach to your hands and cause additional stings and pain. Don’t flush with fresh water, urine, gasoline or turpentine, this will stimulate the tentacles to release more venom.
It is suggested to use a solution of vinegar and warm water to the site to prevent further stings. If vinegar is not available, flush the effect area with copious amounts of salt water. Pick off the remaining tentacles with a stick or your hand protected by a towel or glove. If it is available, apply a lather of shaving cream or soap, or a paste of baking soda, flour, or talc, to the skin. The stinging cells will stick to the shaving cream or paste and can then be easily scraped off with the edge of a credit card.
Closely observe the victim for any signs of a serious allergic reaction. Any swelling of the neck, face, tongue, developing hives and skin rashes or difficulty in breathing could be the beginning signs of anaphylactic shock and should be treated by a medical professional immediately.