Overview
Walking on a beach or swimming in the ocean can be fun and relaxing. But just like with any other activities, injuries can happen. This topic gives an overview of jellyfish and Portuguese man-of-war stings, seabather's eruption, and coral scrapes.
Stings
Jellyfish and Portuguese man-of-wars are members of a large group of venomous marine animals that also includes fire coral and sea anemones. They can be found all over the world. They cause injury and illness through the release of venom when their tentacles come in contact with skin (stinging). Tentacles are long, slender, flexible growths found on jellyfish, Portuguese man-of-wars, squid, and octopuses. Tentacles are used for grasping, feeling, moving, and killing prey by stinging. While the sting of a jellyfish or Portuguese man-of-war can cause severe illness and extreme pain, documented deaths are rare.
Jellyfish are often found in coastal waters, having been brought ashore by winds or ocean currents. They are most common in warm ocean waters, especially along the Atlantic coast of the United States. Stings result from contact with the tentacles, which trail from the jellyfish's see-through body. It's often hard to see jellyfish swimming in the water. Beached jellyfish, which may look like a clear plastic wrapper, can sting if touched.
Jellyfish stings cause intense pain and burning right away. The pain can last for several hours. Raised, red welts form along the site of the sting. It may look like you've been hit with a whip. The welts may last for 1 to 2 weeks, and itchy skin rashes may appear 1 to 4 weeks after the sting.
Most jellyfish stings aren't severe. Extensive stings, allergic reactions, and severe reactions aren't common, but they do occur. To avoid the risk of drowning, swimmers should get out of the water as soon as they realize they've been stung.
The box jellyfish, which is found in the Indian Ocean and South Pacific, can cause a fatal reaction. It is the only jellyfish for which a specific antidote (antivenom) exists. If you get this antivenom, it may save your life.
Seabather's eruption is a rash from the stings of jellyfish or sea anemone larvae. The rash can be quite itchy and annoying. But it usually goes away without medical treatment in 10 to 14 days.
Portuguese man-of-wars (hydrozoans) live in warm seas throughout the world but are most common in the tropical and subtropical regions of the Pacific and Indian oceans and in the Gulf Stream of the North Atlantic Ocean. They float on the surface of the water with their long, stinging tentacles trailing in the water below. Detached tentacles that wash up on the beach may remain dangerous for months.
Portuguese man-of-war stings produce immediate burning pain and redness where the tentacles touched the skin. The affected area develops a red line with small white lesions. In severe cases, blisters and welts that look like a string of beads may appear. Stings that involve the eye may cause pain, swelling, excessive tears, blurred vision, or increased sensitivity to light. Severe reactions are most likely to occur in children and small adults. Severe toxic reactions to the venom can also occur.
Stingrays are members of the shark family. They have sharp spines in their tails that can cause cuts or puncture wounds. The spines also have venom. Stingrays don't bite, but they can suck with their mouths and leave a bruise.
Coral scrapes
Coral scrapes and cuts are common injuries that may occur when you walk on a beach or swim, snorkel, or dive in warm water. Coral polyps, the soft living material that covers the surface of coral, can be easily torn away from the rigid and abrasive structure underneath if you touch, bump, or fall on coral. You may get a skin infection if small pieces of coral, other debris, and bacteria get inside the wound. Scrapes and cuts from sharp-edged coral may take weeks or even months to heal.
Caring for a jellyfish or Portuguese man-of-war sting
Try these tips for caring for a sting from a jellyfish or Portuguese man-of-war.
- Don't rub.
- Do not rub the tentacles with your hands, a towel, sand, or clothing.
- Numb the area, and wash.
- If you have it, apply topical lidocaine to the sting area.
- Use hot water on the area to help remove the nematocysts, the stinging part of the tentacle.
- If hot water and lidocaine aren't available, remove the nematocysts and wash the area with salt water.
- Don't use urine, gasoline, kerosene, or turpentine.
- Use special care for eye stings.
- Rinse eye stings with a saline solution, such as Artificial Tears.
- Don't put vinegar, alcohol, or any other "stinger solution" in the eyes.
- Dab the skin around the eye with a cloth soaked in vinegar. But be extremely careful to not get any of the solution in the eye.
- Remove the tentacles carefully.
- After decontamination, pick off tentacles with a stick or your hand protected by a towel or glove. Be very careful not to rub or press the tentacles.
- If it's available, apply a lather of shaving cream or soap, or a paste of baking soda, flour, or talc to the skin. The stinging cells will stick to the shaving cream or paste. They can then be easily scraped off with a safety razor, a knife edge, or the edge of a credit card.
- Use ice.
- Using an ice pack can help relieve pain.
- Try medicines to control the itching.
- Take an antihistamine, such as a non-drowsy one like loratadine (Claritin) or one that might make you sleepy like diphenhydramine (Benadryl).
- Apply 1% hydrocortisone cream to help control itching. You may need to check with your doctor first if you need to use the cream for a child younger than age 2 or for use in the genital area.
These medicines may not be safe for children younger than age 6 or for people who have certain health problems. Before you use them, check the label. If you do use these medicines, always follow the directions about how much to use based on age and, in some cases, weight. You may need to check with your doctor about using these medicines.
If a sting leaves open sores, clean them 3 times a day. Apply a thin layer of petroleum jelly (such as Vaseline), and cover with a light bandage.
Caring for coral scrapes and cuts
Try these tips for caring for minor coral scrapes or cuts.
- Wash the wound.
- Clean the wound as soon as you can to reduce the risk of infection, scarring, and tattooing of the skin from coral material left in the wound.
- Wash the wound for 5 minutes with a soft brush or towel and large amounts of warm water and soap (mild dishwashing soap, such as Ivory, works well).
- After washing, rinse the wound with a large amount of fresh water.
- After rinsing with fresh water, rinse the wound again with a solution of one-half hydrogen peroxide and one-half water.
- After rinsing with a solution of one-half hydrogen peroxide and one-half water, rinse again with fresh water.
- Stop bleeding with direct pressure to the wound.
- Apply a non-stick bandage.
- Cover the wound with a thin layer of petroleum jelly, such as Vaseline, and a non-stick bandage.
- Apply more petroleum jelly and replace the bandage as needed.
- Apply a clean bandage when it gets wet or soiled to further help prevent infection.
- If a bandage is stuck to a scab, soak it in warm water to soften the scab and make the bandage easier to remove.
- Watch for symptoms of a skin infection.
Be patient. Coral scrapes and cuts may take weeks and sometimes even months to heal completely.
Caring for seabather's eruption
Here are some self-care tips for seabather's eruption.
- Prevent more stings.
- Don't rub your skin. If larvae are on your skin, rubbing will cause them to sting.
- Remove your swimsuit as soon as you can. Larvae can get trapped in the fabric of your suit. So it's important to remove a contaminated suit to prevent more stings.
- Rinse with vinegar or rubbing alcohol.
- If available, rinse your skin in household vinegar (5% acetic acid solution) or rubbing alcohol (40%–70% isopropyl alcohol).
- Shower with fresh water.
- Apply soap, and vigorously scrub your skin.
- Don't shower with a contaminated suit on. If larvae are trapped in the fabric of a suit, a freshwater shower will cause the larvae to sting.
- Use ice.
- Using an ice pack can help relieve pain.
- Try medicines to control the itching.
- Take an antihistamine. Don't give antihistamines to your child unless you've checked with the doctor first.
- Apply 1% hydrocortisone cream to help control itching. You may need to check with your doctor first if you need to use the cream for a child younger than age 2 or for use in the genital area.
These medicines may not be safe for children younger than age 6 or for people who have certain health problems. Before you use them, check the label. If you do use these medicines, always follow the directions about how much to use based on age and, in some cases, weight. You may need to check with your doctor about using these medicines.
Wash the rash with clean water daily.
When to call for help during self-care
Call a doctor if any of the following occur during self-care at home:
- New or worse trouble breathing.
- New or worse swelling of the lips, tongue, or throat.
- New or worse rash.
- New or worse signs of infection. This may include redness, warmth, swelling, pus, or a fever.
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