Does peeing on a jellyfish sting really help?

Jillian Cole
26 September 2014

Above: image ©

Did you know? Jellyfish do not have a heart, a brain, or even blood! Their bodies are about 95% water. In an iconic episode of the sitcom Friends, Monica gets stung by a jellyfish. In an attempt to come to the rescue, Joey mentions a documentary he recently watched that discussed how peeing on a jellyfish sting will make the pain go away. The “procedure” seemed to help Monica, but does it really work? Before your next beach vacation, here’s what you need to know about jellyfish stings and urine.

First of all, is peeing on a jellyfish sting a good idea? It seems like a strange idea yet so many people seem to think it will help. Survey says: NO! One of the worst things you can do after getting stung by a jellyfish is pee on it. Multiple studies have looked at the effect of urine on injuries like insect and jellyfish stings. Medical professionals have concluded that, if anything, it will make the pain worse and could even lead to infection.

What happens when a jellyfish stings you?

When you are stung by a jellyfish, its tentacles attach to your body and inject venom.This venom contains porin, a type of protein. Porin is what makes a jellyfish sting so uncomfortable and leads to blistering. Some species of jellyfish may inject more venom than others.

Did you know? Certain species of box jellyfish are considered the most dangerous to humans and can have tentacles as long as 3 m. However, the largest species of jellyfish is the Lion’s mane jellyfish, which can have tentacles 80 m long! Most jellyfish stings are minor. However, some can be toxic and might require immediate attention. If you are stung on the face or if a sting covers more than 50% of a body part, it could be serious. If a person who has been stung has problems breathing, find a lifeguard or call for emergency medical assistance immediately.

Peeing on it will probably only make things worse

According to Jennifer Ping, an emergency physician, peeing on a jellyfish sting will make the stinging cells (called cnidoblasts) bigger, increasing the amount of pain. This is because the pH of urine is closer to that of water than a more acidic liquid like vinegar. In fact, rinsing the still with fresh water can also make the pain worse because it reactivates the stinging cells.

A lion's mane jellyfish photographed off the coast of Newfoundland. Click image to enlarge (Wikimedia Commons/derekkeats)

Nevertheless, some studies have suggested peeing on a jellyfish sting might help in other ways. For example, in the case of a 13-year-old boy attacked by a jellyfish, a groups of Mexican researchers found that applying urine the sting had caused the symptoms to go away after only two hours. They concluded that the warmth of the urine helped treat the injury. However, it is important to note that, in this case, the tentacles were removed first. This makes a big difference in how the pee would have interacted with the affected area.

So what should you do?

Dr. Ping explains that the first thing you should do after being stung is get out of the water and find a way to remove the tentacles (don’t use your fingers). Next, some experts recommend disabling the stinging cells by splashing the affected area with an acidic substance like vinegar, although this point is hotly debated in the medical field. Finally, remove the stinging cells using a piece of plastic like a credit card.

Did you know? All jellyfish have stinging cells, but not all of them are strong enough to sting humans. In general, the larger the jellyfish, the more powerful the sting, since larger jellyfish have larger stinging cells. Once the tentacles have been safely removed, a common theory among scientists is that warm water will help. This may be where the idea of peeing on someone comes from. However, the University of Arkansas for Medical Sciences has a very specific list of things never to do after to a jellyfish sting: pee on it, apply vinegar or meat tenderizer, and rub the affected area. Instead, you should wash the sting with salt water because that can deactivate the stinging cells. Never give someone who has been stung by a jellyfish any medicine, including painkillers such as ibuprofen, without checking with a doctor first.

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So before you let someone pee on you, remember the proper safety techniques for dealing with a jellyfish sting! Never use your fingers to remove the tentacles, disable the stinging cells, and remove them immediately with a scraper or other flat surface.

Learn more!

Does Peeing on a Jellyfish Sting Really Work? (2012)

Natalie Wolchover,

An explanation of why peeing on a jellyfish sting is normally not a good idea.

Does urine help a jellyfish sting? (2014)

University of Arkansas for Medical Sciences

A short explanation of what to do (and especially what not to do) to treat a jellyfish sting.

Evolution Of A Jellyfish Sting Treated With Urine (2012)

A. Orozco-Gutiérrez, J. Nuñez del Prado, C. Calderón-Jiménez and C. Gil-Rosales. The Internet Journal of Emergency and Intensive Care Medicine 12(2)

A paper discussing the treatment of a 13 year old boy stung by a jellyfish, suggesting that applying urine may have some benefits after the tentacles have been removed.

What’s Behind That Jellyfish Sting? (2013)

Emily Frost,

An explanation of what happens when you are stung by a jellyfish and what to do about it.

How Jellyfish Work (2014)

Stephanie Watson, HowStuffWorks

An introduction to jellyfish behaviour and different species of jellyfish, with links to additional information.

Jillian Cole

Hello! I am a fifth year university student, doing a combined program of Marine Biology and Environmental Impact Assessment for a Bachelor of Science. I love anything and all things related to the ocean, but especially the creatures within.

Some of my favourite species include: sea stars, cuttlefish, the sea worm Amphitre johnstoni, and of course all members of the whale family. 
I love science because it gives you an inside view on the way animals act within their environments.

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