What is the recommended immediate rinsing agent for many common jellyfish stings to neutralize unfired nematocysts?
Vinegar (acetic acid).
The consensus for immediate first aid for many common jellyfish stings favors using vinegar, which is acetic acid. The primary function of vinegar in this initial rinsing step is not to treat the pain or neutralize venom already injected, but rather to chemically neutralize the unfired nematocysts still embedded in or resting on the skin. By neutralizing these barbs chemically, vinegar effectively prevents the mechanism from deploying, thus halting the injection of further venom. This step is critical for managing the ongoing risk immediately after the initial contact. However, it is noted that this treatment is contraindicated for certain species, like the Portuguese Man-of-War, where vinegar application may worsen the sting.
