In hot water over bluebottles

By Virginia Winder

You’re diving under a frothy wave at the beach when you feel a sharp burning along your leg.

In the lull between waves, you notice a blue tentacle stuck to your knee and calf, so you use the seawater to frantically rub it off.

The tentacle has gone but the burning becomes more intense, so you head for shore realising you’ve been stung by a bluebottle.

So what do you do?

My guesses are you’ll think cold water, ice, vinegar or even aloe vera will help. Well you’d be wrong. Absolutely off the mark. Completely amiss.

I’m writing this because there has been a swarm of these weird-looking blue-bladder sea creatures at Oakura and signs of it at other beaches in Taranaki.

I’m also writing because I’m sick of the wrong advice being given to people about what to do.

The answer is, according to both the National Poisons Centre and the Ministry of Health (MoH) website, that the best way to treat bluebottle stings is with hot water.

In fact, the MoH recommends immersing the part of your body that’s been stung into water 45 degrees Celsius for up to 20 minutes. Showers also work.

I’ve had a sting. The long tentacle of a bluebottle, which can reach up to 10 metres in length, wrapped around my hand like blue thread. After I washed it off, my hand felt like it was on fire.

I went home and immersed myself in a shower as hot as I could bear it. My nephew was stung on his torso and we gave him the hot water treatment too and the pain disappeared miraculously.  

What happens, says Leo Schep from the National Poisons Centre, is the hot water “denatures” the sting. In layperson’s terms that means the heat changes the structure of the venom, which is a protein. Hot water does that in much the same way as cooking an egg white, causing the pain to immediately stop.

“Don’t use vinegar, because that will just make it release more of the venom,” he says.

The MoH backs this up in its treatment for jellyfish stings.

“If you can get vinegar, pour this over the stung area (but do not use vinegar for bluebottle stings),” its website says.

So there you have it – hot water is the answer to a close encounter with a blue stinger.

This comes from the experts and personal experience.

Cook that venom!