These stings cause pain, blisters, and skin necrosis or cell death. People who’ve been stung may have weakness, fever, chills, muscle spasms, nausea, and vomiting. In rare cases, some types of jellyfish, such as the Chironex fleckeri box jellyfish in Australia, can cause paralysis and death.
This gallery shows what different stings can look like. It also explains how they should (and shouldn’t) be treated.
Burning, prickling, or stingingItchingSwellingA throbbing pain shooting up a leg or arm
Jellyfish stings can usually be diagnosed by how they look. They are often mistaken for stings from other sea creatures, including:
Portuguese man o’ warsBlue bottlesPuffer fishSea anemones
Tylenol (acetaminophen) or OTC nonsteroidal anti-inflammatory drugs (NSAIDs) like Advil (ibuprofen) or Aleve (naproxen) can ease pain.
The first step in treating the sting is to remove any parts of the tentacle still attached to the skin—but not with your bare hands. Even if the tentacle is no longer attached to the creature, it can keep injecting toxins. The best ways to remove a tentacle are with gloves, a brush, or the edge of a credit card.
Others insist that the body part should be soaked for 20 to 45 minutes in hot water 110 to 113 F (43 to 45 C) to draw out the toxins. If there are any stingers still in the skin, you can pluck them out with tweezers.
Some people use all of these methods, soaking the skin in vinegar for 30 seconds before removing the remaining stingers. Then they follow with soaking for 20 to 40 minutes in hot but not scalding water.
Using a cold compress after the soak may help ease the pain and inflammation.
Pufferfish stings are more spread out. The marks are irregular with a cluster of raised sores. Anemone stings are similar, but more tightly clustered. They sometimes develop blister-like sores that ooze.
Learning the difference between these types of stings can help you get the right treatment. Some stings, like those from a man o’ war, can be severe.
An ophthalmologist or eye doctor will need to remove any stingers and assess the injury. You may need oral antibiotics to prevent infection and reduce the risk of eye damage.
Rinse a sting with urineApply meat tenderizerApply alcohol or ammoniaApply pressure bandagesRub the skin with sandRub the skin with seaweedSoak the skin with cool, fresh water or sea water, which can release even more venom
The type of jellyfishThe number of stingsThe amount of skin affectedThe length of time you were exposedYour age, general health, and medical conditions such as heart problems or a history of anaphylaxis
Summary
Jellyfish stings involve thousands of jabs, each of which releases toxins. They can cause pain, swelling, redness, and itching. For some people, they can also cause an allergic reaction that can be life-threatening.
To tell a jellyfish sting from other sea creature stings, look for narrow trails of tentacle marks. A wide trail or one with random clusters is likely to be the sting of a different creature.
You’ll need to remove any stingers left in the skin. If the sting isn’t severe, it can probably be treated at home with distilled white vinegar, a hot water soak, or both. If you start to have breathing problems, a racing heartbeat, or swelling, it’s time to go to an urgent care clinic or the emergency room.
Next, soak the sting in hot water to draw out the venom. The water should feel hot but not scalding. Soak the injured skin for 20 to 45 minutes.
