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You’ve probably heard the suggestion to pee on a jellyfish sting to take away the pain. And you've likely wondered if it really works. Or you may have questioned why urine would be an effective treatment for a sting.

In this article, we'll take a closer look at the facts and help uncover the truth behind this common suggestion.

Quite simply, no. There is no truth to the myth that peeing on a jellyfish sting can make it feel better. Numerous studies have found that this simply doesn't work.

One of the possible reasons that this myth became popular could be due to the fact that urine contains compounds like ammonia and urea. If used alone, these substances may be helpful for some stings. But your pee contains a lot of water. And all that water dilutes the ammonia and urea too much to be effective.

What's more, the sodium in your urine, together with the velocity of the urine stream could move the stingers around in the injury. This could trigger the stingers to release even more venom.

Here's what happens when you get stung by a jellyfish:

  • Jellyfish have thousands of tiny cells on their tentacles (known as cnidocytes) that contain nematocysts. They're like tiny capsules that contain a sharp, straight, and narrow stinger that's tightly coiled and armed with venom.
  • The cells on the tentacles can be activated by an outside force that makes contact with them, such as your arm brushing against a tentacle, or your foot smashing a dead jellyfish on the beach.
  • When activated, a cnidocyte pops open and fills with water. This added pressure forces the stinger out of the cell and into whatever triggered it, like your foot or arm.
  • The stinger releases venom into your flesh, which can get into tissues and blood vessels that it pierces.

This all happens incredibly quickly — in as little as 1/10 of a second.

The venom is what causes the sharp pain you experience when a jellyfish stings you.

Most jellyfish stings are harmless. But there are some types of jellyfish that contain poisonous venom that can be dangerous if you don't get immediate medical attention.

Some common, and less serious, jellyfish sting symptoms include:

  • pain that feels like a burn or prickling sensation
  • visible colored marks where the tentacles touched you that are usually a purple, brown, or reddish color
  • itchiness at the sting site
  • swelling around the sting area
  • throbbing pain that spreads beyond the sting area into your limbs

Some jellyfish sting symptoms are much more severe. Seek emergency medical attention if you experience any of the following symptoms:

  • stomach pain, vomiting and nausea
  • muscle spasms or muscle pain
  • weakness, drowsiness, confusion
  • fainting
  • trouble breathing
  • heart issues, such as rapid or irregular heartbeat (arrhythmia)

How to treat a jellyfish sting

  • Remove visible tentacles with fine tweezers. Pluck them out carefully if you can see them. Don't try to rub them off.
  • Wash tentacles off with sea water and not fresh water. Fresh water may actually trigger the release of more venom if any tentacles still remain on the skin.
  • Apply a pain-relieving ointment like lidocaine to the sting, or take an over-the-counter painkiller like ibuprofen (Advil).
  • Use an oral or topical antihistamine like diphenhydramine (Benadryl) if you think you may be allergic to the sting.
  • Do not rub your skin with a towel, or apply a pressure bandage to the sting.
  • Rinse and soak the sting with hot water to reduce the burning sensation. Taking a hot shower right away, and keeping a stream of hot water on your skin for at least 20 minutes, may be helpful. The water should be around 110 to 113°F (43 to 45°C). Remember to remove tentacles first before doing this.
  • Get to a hospital immediately if you have a severe or life-threatening reaction to a jellyfish sting. A more serious reaction will need to be treated with jellyfish antivenin. This is only available at hospitals.

Some jellyfish are relatively harmless, but others can have deadly stings. Here's a summary of the types of jellyfish you may run into, where they are typically found, and how severe their stings are:

  • Moon jelly (Aurelia aurita): A common but harmless jellyfish whose sting is typically mildly irritating. They are found in coastal waters around the world, mostly the Atlantic, Pacific, and Indian oceans. They are commonly found on the coasts of North America and Europe.
  • Portuguese man-o-war (Physalia physalis): Found mostly in warmer seas, this species floats on the surface of the water. While its sting is rarely deadly to people, it can cause intense pain and welts on exposed skin.
  • Sea wasp (Chironex fleckeri): Also known as box jellyfish, this species lives in the waters around Australia and Southeast Asia. Their sting can cause intense pain. Although rare, the sting of this jellyfish can cause life threatening reactions.
  • Lion's mane jellyfish (cyanea capillata): Found mostly in the cooler northern regions of the Pacific and Atlantic oceans, these are the world's largest jellyfish. Their sting can be deadly if you're allergic to it.

  • Don't ever touch a jellyfish, even if it's dead and lying on the beach. The tentacles can still trigger their nematocysts even after death.
  • Talk to lifeguards or other safety personnel on duty to see if any jellyfish have been spotted or if stings have been reported.
  • Learn how jellyfish move. They tend to go along with ocean currents, so learning where they are and where the currents are taking them can help you avoid a jellyfish encounter.
  • Wear a wetsuit or other protective clothing when you're swimming, surfing, or diving to protect your bare skin from brushing against jellyfish tentacles.
  • Swim in shallow waters where jellyfish usually don't go.
  • When walking into the water, shuffle your feet slowly along the bottom of the water. Disturbing the sand may help you avoid catching sea critters, including a jellyfish, by surprise.

Don't believe the myth that peeing on a jellyfish sting can help. It can't.

There are multiple other ways to treat a jellyfish sting, including removing tentacles from your skin and rinsing with sea water.

If you have a more severe reaction, like difficulty breathing, a rapid or irregular heartbeat, muscle spasms, vomiting, or confusion, get medical attention right away.