Don't let the coy name fool you; these are nasty guys - stinging hydroids, fire
coral (not a true coral) and jellyfish. Their weapons are nematocysts, stinging
cells filled with venom and a coiled thread adorned with a barb at its
business end. When triggered, the nematocyst fires and harpoons you with
enough force to penetrate your skin and inject venom.
Hydroids such as fire coral produce an immediate burning sensation
followed within 30 minutes by an itchy rash that takes several days to heal.
Jellyfish stings cause burning and leave a trail of bumps and welts. Serious
jelly encounters can result in a severe burning sensastion, muscle spasms,
vomiting, shock, even collapse.
Remove tentacles with a gloved hand or tweezers to keep from
getting stung and then rinse thoroughly with salt water. Fresh water or
rubbing will trigger unfired nematocysts.
Deactivate remaining nematocysts with a 5 percent vinegar solution
until the stinging stops. Use isopropyl alcohol if you don't have
vinegar. Meat tenderizer also neutralizes venom - add some to the
solution if you have it.
Apply shaving cream and scrape skin with a razor to remove
nematocysts. A paste of mud, flour or talc scraped with a dive knife
or credit card also works.
Dry the skin and apply hydrocortisone ointment and take a
diphenhydramine preparation (like Benadryl) for mild allergic
Keep the victim still to prevent venom from spreading, with the
injured part elevated above the heart.
Serious stings that result in life-threatening reactions like spasms,
breathing difficulty and shock require emergency medical attention.