What is treatment for jellyfish sting?

Answer 1

The best treatment is:

Wash it with clean water. Do not rub it, as the tiny stinging cells will release more venom. After washing, apply household ammonia. You might also take a Benadryl (diphenhydramine) tablet to reduce the inflammation. (From a former ocean lifeguard.)

Answer 2

Vinegar (3-10% aqueous acetic acid) may be used as a common remedy to help with box jellyfish stings. Salt water may be used as an alternative if vinegar is unavailable.

Clearing the area of jelly, tentacles, and wetness further reduces nematocyst firing. Scraping the affected skin with a knife edge, safety razor, or credit card may remove remaining nematocysts.

Beyond initial first aid, antihistamines such as diphenhydramine (Benadryl) may control skin irritation (pruritus). Immunobased antivenins have been available since the 1970s.