8 Things to Do if You Encounter a Jellyfish

There’s something outer-worldly about jellyfish. Their translucent bodies, the dangling tentacles floating in their wake, the way they glide elegantly through the water—it’s sometimes hard to believe that these beautiful specimens are living creatures.

But they are living things—in fact, they are living things that are perfectly capable of delivering a shockingly painful (and possibly lethal) sting.

Jellyfish tend to stay towards the surface of the ocean, so if you’re swimming or snorkeling in jellyfish territory, you need to know what to do if you encounter one up close. Here are a few things to keep in mind.

The Stinging Secret
The secret to the jellyfish’s sting lies within the cells on its tentacles. When a jellyfish’s tentacles come into contact with human skin, stinging structures located in their cells can pierce the skin, releasing poison into the victim. Note that the tentacle has to contact the skin directly in order to release the poison, so wearing a stinger suit or a wet suit will help prevent stings.

Signals of Severity
A jellyfish sting can range in severity, depending on the type of jellyfish. Most aren’t lethal, but a few are: some species, including the box jellyfish (most commonly found in and near Australia), can deliver a sting strong enough to kill a human in just a few minutes.

Avoid an Encounter
If you’re in an area where it is known that jellyfish like to hang out, skip the swim altogether. Keep your eyes peeled for warning signs on beaches, or ask locals about conditions.

Approach With Caution
If you see a jellyfish, be careful of getting too close. This remains true for beached and dying jellyfish, since they can still deliver a powerful sting. That seemingly dead sac of air half-buried in the sand might look harmless, but it’s not!

Don’t Panic
If you see a jellyfish in the water, stay cool. If possible, swim calmly away from the jellyfish towards shore. If there is no escape, tread slowly and hope that the jellyfish passes you by. Most jellyfish only sting when they are provoked.

If Someone Is Stung
The protocol for a jellyfish sting is relatively straightforward. The first priority is to get the victim out of the water as soon as possible, without touching the affected area. Don’t let them scratch—this could worsen the stinging. Wash the sting site with warm saltwater to help stop the stinging.

Next, it’s time to remove the tentacles: something sturdy, like an angled credit card, tweezers, or even sticks if nothing else is available, can be used to scrape gently across the skin to detach any stuck tentacles. If you use your hands to remove the tentacles, be sure to wear gloves– or else you, too, could end up stung! Clean and bandage open sores and treat the patient with antihistamines, and seek medical attention if necessary.

Call For Help ASAP If…
There are three jellyfish related incidents where you should absolutely call 911 without delay. The first: if the area affected by the sting affects more than half an arm or half a leg. The second: if the victim displays signs of a severe allergic reaction, like difficulty breathing, chest pains, or the swelling of the tongue or lips. An anaphylactic reaction to a jellyfish sting can be lethal. Finally: if you suspect the sting is from a box jellyfish, get help immediately.

What Not To Do
Ignore what you’ve seen on TV: urinating on a sting is not an effective treatment. Neither is applying fresh water to the wound.
For many years, many sources (including the American Red Cross) suggested rinsing with vinegar, but recent studies have shown that this might not always be effective. In fact, the research indicated that vinegar can actually make the stinging worse. Some people still swear by the vinegar method, but it doesn’t hurt to know both signs of the argument.