First Aid Bites & Stings Print Jellyfish Sting Pictures What They Look Like and How to Treat Them By Rod Brouhard, EMT-P Updated March 31, 2019 More in First Aid Bites & Stings Allergies & Anaphylaxis Breathing Emergencies Broken Bones Bruises, Cuts & Punctures Heat & Cold Exposure Infections Rash Emergency Preparedness Calling for Help View All Cnidarian, or jellyfish, stings are a common cause of emergency room visits in tropical coastal regions. Cnidarians have tentacles containing thousand of stinging cells, called nematocytes, that fire toxins upon physical contact. Symptoms include intense pain, blistering, and localized skin necrosis (cell death). Malaise, weakness, fever, chills, muscle spasms, nausea, and vomiting may also occur. On rare occasion, certain types of jellyfish (such as the Chironex fleckeri box jellyfish in Australia) can cause paralysis and even death. 1 Jellyfish Sting on Knee Erin/Flickr Creative Commons Jellyfish stings have a distinctive look. The sting will commonly leave a "print" of the tentacle with red, brown, or purplish track marks along the skin. The physical markings will usually be accompanied by: Burning, prickly, or stinging sensationsItchingLocalize swellingA throbbing pain radiating up up a leg or arm Jellyfish stings can usually be diagnosed by appearance alone, although they are often mistaken for stings from other sea creatures, including Portuguese man o' wars, blue bottles, puffer fish, and sea anemones. Seek emergency care if you develop signs of a potentially life-threatening allergy known as anaphylaxis, including shortness of breath, hives, rapid heartbeat, nausea, confusion, and the swelling of the face, tongue, or throat. 2 Jellyfish Sting on Knee After 2 Days Erin/Flickr Creative Commons Two days after a jellyfish sting, the skin will have undergone healing but will still show evidence of the tentacle marks. A rash or other skin reaction can sometimes develop due to a delayed hypersensitivity reaction. These can usually be treated with oral antihistamines or corticosteroids. Tylenol (acetaminophen) or over-the-counter nonsteroidal anti-inflammatory drugs (NSAIDs) like Advil (ibuprofen) or Aleve (naproxen) can help relieve the pain 3 Jellyfish Sting on the Torso Pete & Brook Contact with a jellyfish tentacle can trigger thousands of nematocysts to pierce the skin and inject toxins. Depending on the species and the number of stings delivered, the reactions can range from mild to severe. If there are multiple stings, the venom can sometimes consolidate in the capillaries and cause area of patchy redness, swelling, and a burning sensation. The first step in treating a jellyfish 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 contracting and injecting toxins into the skin. The best ways to remove a tentacle is with gloves, a brush, or even the edge of a credit card. Basic First Aid Procedures You Should Know 4 Jellyfish Sting on Arm Kate Nevens/Flickr Creative Commons There is an ongoing debate about the best way to treat a jellyfish sting. In one camp, there are those who insist that distilled white vinegar will "neutralize" the toxins. 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 remaining stingers in the skin, you can use a pair of tweezers to pluck them out. Some people will use all of these methods, soaking the skin in vinegar for 30 seconds before removing the remaining stingers, followed by 20 for 40 minutes in hot (not scalding) water. Using a cold compress after the initial treatment may help alleviate some of the pain and inflammation. 5 Man-O-War Sting Portuguese man o' war sting. Simon Tonge/Flickr Creative Commons Jellyfish stings can be distinguished from other stings by the narrow trail of tentacle marks they leave. Other jellyfish-like creatures, such as the Portuguese man o' war, tend to leave wider marks on the skin and larger areas of redness, swelling, inflammation. Pufferfish stings, by contrast, are more diffuse and irregular in their markings with a localized cluster of raised lesions. Anemone stings are similar but will be more tightly clustered and sometimes develop leave blister-like lesions that ooze. Learning the difference between the various sea creature stings can ensure the most appropriate treatment and care. Some stings, like those from a man o' war, can be especially severe. While man o' war stings can cause extreme pain, they are rarely deadly. Far more serious is the box jellyfish of Australia which has caused eight deaths since 2000 (two in 2016 alone). 6 Jellyfish Sting to the Neck Mat Honan Jellyfish stings to the face or head will usually not leave scars if treated appropriately. The only concern is if a sting occurs in or around the eye. In such case, it is important that you thoroughly flush the eye with water and either go to the nearest emergency room or call 911 if you can't drive yourself. An ophthalmologist will most likely need to see you to remove any remaining stingers and assess the injury. Oral antibiotics will usually be prescribed to prevent infection and reduce the risk of eye damage. 7 Sea Anemone Sting Sea anemone sting. Missi Bellande/Flickr Creative Common Whatever the cause of the sting, there are home-spun remedies you should avoid to keep a bad situation from turning worse. Among the things to avoid: Rinsing a sting with urineApplying meat tenderizerApplying alcohol or ammoniaApplying pressure bandagesRubbing the skin with sandRubbing the skin with seaweedSoaking the skin with fresh water (which can release even more venom) 8 Jellyfish Sting on the Feet bobafred/Flickr Creative Common Most jellyfish stings do not require medical care and can be effectively treated at home. With that being said, the severity of a sting can vary based upon: The type of jellyfish you encounterThe number of stings you incurThe amount of skin affectedThe duration of the exposure Your age, general health, and medical conditions (such as a heart problem or a history of anaphylaxis) Because of their smaller size, young children are prone to more serious reactions and should always be seen by a doctor. Reactions may appear rapidly or several hours after the sting. Jellyfish Treatment Myths Was this page helpful? Thanks for your feedback! Sign up for our Health Tip of the Day newsletter, and receive daily tips that will help you live your healthiest life. Email Address Sign Up There was an error. Please try again. Thank you, , for signing up. What are your concerns? Other Inaccurate Hard to Understand Submit Article Sources Gershwin, L.; Condie, S.; Mansbridge, J. et al. Dangerous jellyfish blooms are predictable. J Royal Soc Interface. 2014;11(96):20131168. DOI: 10.1098/rsif.2013.1168. Ping, J. and Onizuka, N. Epidemiology of Jellyfish Stings Presented to an American Urban Emergency Department. Hawaii Med J. 2011;70(10):217-9.