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Marine Stings and Scrapes
Walking on a beach or swimming in the ocean can be fun and relaxing. But just like any other activities, accidents can happen. This topic will help you determine the next steps to take if you have a jellyfish or Portuguese man-of-war sting, seabather's eruption, or a coral scrape.
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 are present all over the world and 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 present 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. Jellyfish swimming in the water are often hard to see. Beached jellyfish, which may look like the cellophane wrapper from a cigarette pack, can sting if touched.
Jellyfish stings cause immediate, intense pain and burning that can last for several hours. Raised, red welts develop along the site of the sting, which may look like you have 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. Fortunately, most jellyfish stings are not severe. Extensive stings, allergic reactions, or severe reactions are not common but do occur. To avoid the risk of drowning, swimmers should get out of the water as soon as they realize they have 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 that develops 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 do not bite but can suck with their mouths and leave a bruise.
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. A skin infection may develop when 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.
Check your symptoms to decide if and when you should see a doctor.
Check Your Symptoms
The medical assessment of symptoms is based on the body parts you have.
- If you are transgender or nonbinary, choose the sex that matches the body parts (such as ovaries, testes, prostate, breasts, penis, or vagina) you now have in the area where you are having symptoms.
- If your symptoms aren’t related to those organs, you can choose the gender you identify with.
- If you have some organs of both sexes, you may need to go through this triage tool twice (once as "male" and once as "female"). This will make sure that the tool asks the right questions for you.
Many things can affect how your body responds to a symptom and what kind of care you may need. These include:
- Your age. Babies and older adults tend to get sicker quicker.
- Your overall health. If you have a condition such as diabetes, HIV, cancer, or heart disease, you may need to pay closer attention to certain symptoms and seek care sooner.
- Medicines you take. Certain medicines, such as blood thinners (anticoagulants), medicines that suppress the immune system like steroids or chemotherapy, herbal remedies, or supplements can cause symptoms or make them worse.
- Recent health events, such as surgery or injury. These kinds of events can cause symptoms afterwards or make them more serious.
- Your health habits and lifestyle, such as eating and exercise habits, smoking, alcohol or drug use, sexual history, and travel.
Try Home Treatment
You have answered all the questions. Based on your answers, you may be able to take care of this problem at home.
- Try home treatment to relieve the symptoms.
- Call your doctor if symptoms get worse or you have any concerns (for example, if symptoms are not getting better as you would expect). You may need care sooner.
Pain in adults and older children
- Severe pain (8 to 10): The pain is so bad that you can't stand it for more than a few hours, can't sleep, and can't do anything else except focus on the pain.
- Moderate pain (5 to 7): The pain is bad enough to disrupt your normal activities and your sleep, but you can tolerate it for hours or days. Moderate can also mean pain that comes and goes even if it's severe when it's there.
- Mild pain (1 to 4): You notice the pain, but it is not bad enough to disrupt your sleep or activities.
Pain in children under 3 years
It can be hard to tell how much pain a baby or toddler is in.
- Severe pain (8 to 10): The pain is so bad that the baby cannot sleep, cannot get comfortable, and cries constantly no matter what you do. The baby may kick, make fists, or grimace.
- Moderate pain (5 to 7): The baby is very fussy, clings to you a lot, and may have trouble sleeping but responds when you try to comfort him or her.
- Mild pain (1 to 4): The baby is a little fussy and clings to you a little but responds when you try to comfort him or her.
Symptoms of infection may include:
- Increased pain, swelling, warmth, or redness in or around the area.
- Red streaks leading from the area.
- Pus draining from the area.
- A fever.
Symptoms of difficulty breathing can range from mild to severe. For example:
- You may feel a little out of breath but still be able to talk (mild difficulty breathing), or you may be so out of breath that you cannot talk at all (severe difficulty breathing).
- It may be getting hard to breathe with activity (mild difficulty breathing), or you may have to work very hard to breathe even when you’re at rest (severe difficulty breathing).
Symptoms of a severe allergic reaction (anaphylaxis) may include:
- The sudden appearance of raised, red areas (hives) all over the body.
- Rapid swelling of the throat, mouth, or tongue.
- Trouble breathing.
- Passing out (losing consciousness). Or you may feel very lightheaded or suddenly feel weak, confused, or restless.
A severe reaction can be life-threatening. If you have had a bad allergic reaction to a substance before and are exposed to it again, treat any symptoms as an emergency. Even if the symptoms are mild at first, they may quickly become very severe.
Certain health conditions and medicines weaken the immune system's ability to fight off infection and illness. Some examples in adults are:
- Diseases such as diabetes, cancer, heart disease, and HIV/AIDS.
- Long-term alcohol and drug problems.
- Steroid medicines, which may be used to treat a variety of conditions.
- Chemotherapy and radiation therapy for cancer.
- Other medicines used to treat autoimmune disease.
- Medicines taken after organ transplant.
- Not having a spleen.
You may need a tetanus shot depending on how dirty the wound is and how long it has been since your last shot.
- For a dirty wound that has things like dirt, saliva, or feces in it, you may need a shot if:
- You haven't had a tetanus shot in the past 5 years.
- You don't know when your last shot was.
- For a clean wound, you may need a shot if:
- You have not had a tetanus shot in the past 10 years.
- You don't know when your last shot was.
Shock is a life-threatening condition that may quickly occur after a sudden illness or injury.
Adults and older children often have several symptoms of shock. These include:
- Passing out (losing consciousness).
- Feeling very dizzy or lightheaded, like you may pass out.
- Feeling very weak or having trouble standing.
- Not feeling alert or able to think clearly. You may be confused, restless, fearful, or unable to respond to questions.
Shock is a life-threatening condition that may occur quickly after a sudden illness or injury.
Babies and young children often have several symptoms of shock. These include:
- Passing out (losing consciousness).
- Being very sleepy or hard to wake up.
- Not responding when being touched or talked to.
- Breathing much faster than usual.
- Acting confused. The child may not know where he or she is.
Call 911 Now
Based on your answers, you need emergency care.
Call 911 or other emergency services now.
Sometimes people don't want to call 911. They may think that their symptoms aren't serious or that they can just get someone else to drive them. Or they might be concerned about the cost. But based on your answers, the safest and quickest way for you to get the care you need is to call 911 for medical transport to the hospital.
Seek Care Today
Based on your answers, you may need care soon. The problem probably will not get better without medical care.
- Call your doctor today to discuss the symptoms and arrange for care.
- If you cannot reach your doctor or you don't have one, seek care today.
- If it is evening, watch the symptoms and seek care in the morning.
- If the symptoms get worse, seek care sooner.
Seek Care Now
Based on your answers, you may need care right away. The problem is likely to get worse without medical care.
- Call your doctor now to discuss the symptoms and arrange for care.
- If you cannot reach your doctor or you don't have one, seek care in the next hour.
- You do not need to call an ambulance unless:
- You cannot travel safely either by driving yourself or by having someone else drive you.
- You are in an area where heavy traffic or other problems may slow you down.
Make an Appointment
Based on your answers, the problem may not improve without medical care.
- Make an appointment to see your doctor in the next 1 to 2 weeks.
- If appropriate, try home treatment while you are waiting for the appointment.
- If symptoms get worse or you have any concerns, call your doctor. You may need care sooner.
Home treatment can help ease your discomfort and prevent other problems.
Jellyfish and Portuguese man-of-war stings
- Do not rub the tentacles with your hands, a towel, sand, or clothing.
- Use hot water on the area to help remove the nematocysts, the stinging part of the tentacle. If available, topical lidocaine can be applied to the sting area.
- If hot water and lidocaine are not available, remove the nematocysts and wash the area with salt water.
- For some types of jellyfish stings, a compress of household vinegar (5% acetic acid solution) and hot water can be used on the affected area to prevent further stings.
- Do not use urine, gasoline, kerosene, or turpentine.
- Rinse eye stings with a saline solution, such as Artificial Tears. Do not put vinegar, alcohol, or any other "stinger solution" in the eyes. The skin around the eye can be dabbed with a cloth soaked in vinegar, but you must be extremely careful not to get any of the solution in the eye.
- 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 is 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 and can then be easily scraped off with a safety razor, a knife edge, or the edge of a credit card.
- Take an antihistamine, such as a nondrowsy one like loratadine (Claritin) or one that might make you sleepy like diphenhydramine (Benadryl), or apply 1% hydrocortisone cream to help control itching. Note: Do not use the cream on children younger than age 2 unless your doctor tells you to. Do not use in the rectal or vaginal area in children younger than age 12 unless your doctor tells you to. Also, don't give antihistamines to your child unless you've checked with the doctor first.
- Use an ice pack to help relieve pain.
- Clean any open sores 3 times per day, apply a thin layer of petroleum jelly (such as Vaseline), and cover with a light bandage.
- Do not rub your skin. If larvae are on your skin, rubbing will cause them to sting.
- Remove your swimsuit as soon as possible. Since larvae can become trapped in the fabric of your suit, it is important to remove a contaminated suit to prevent more stings.
- If available, rinse 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. Do not 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.
- Take an antihistamine, such as a nondrowsy one like loratidine (Claritin) or one that might make you sleepy like diphenhydramine (Benadryl), or apply 1% hydrocortisone cream cream to help control itching. Note: Do not use the cream on children younger than age 2 unless your doctor tells you to. Do not use in the rectal or vaginal area in children younger than age 12 unless your doctor tells you to. Also, don't give antihistamines to your child unless you've checked with the doctor first.
- Use an ice pack to help relieve pain.
- Wash the rash with clean water daily.
Coral scrapes and cuts
Most minor coral scrapes or cuts can be treated at home.
- 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). Cleaning the wound as soon as possible may reduce the risk of infection, scarring, and tattooing of the skin from coral material left in the wound.
- 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.
- You may cover the wound with a thin layer of petroleum jelly, such as Vaseline, and a nonstick 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.
Try a nonprescription medicine to help treat your fever or pain:
Talk to your child's doctor before switching back and forth between doses of acetaminophen and ibuprofen. When you switch between two medicines, there is a chance your child will get too much medicine.
Be sure to follow these safety tips when you use a nonprescription medicine:
Symptoms to watch for during home treatment
Call your doctor if any of the following occur during home treatment:
You can limit your risk of being injured by jellyfish, a Portuguese man-of-war, or coral.
- Be familiar with the marine risks in the area where you plan to swim, snorkel, or dive. If you are traveling, obtain information about the local conditions.
- Be prepared with first aid supplies that might be needed for a injury.
- Watch for warning signs that are posted when there is a jellyfish or Portuguese man-of-war invasion.
- Do not touch jellyfish, Portuguese man-of-wars, or coral.
- Watch out for jellyfish and Portuguese man-of-wars in the water, particularly when there are strong onshore winds.
- Stay out of the water when jellyfish and Portuguese man-of-wars are present. Look out for the bluish floats of the Portuguese man-of-war, and avoid the poisonous trailing tentacles.
- Watch for beached jellyfish and Portuguese man-of-wars. Their tentacles may still sting.
- Do not rely on clothing or on coating the skin with petroleum jelly (such as Vaseline) to prevent stings. Wear a wet suit to reduce your risk of getting stung. A wet suit is a close-fitting, one- or two-piece suit, usually made of rubber or foam neoprene. Swimmers, snorkelers, divers, kayakers, and other people who spend time in cold water may wear wet suits for warmth and protection.
- Wear protective shoes when walking on the beach. Avoid stepping on marine life.
- Avoid swimming or snorkeling in swallow water, where touching or bumping into coral might occur.
- Wash your swimsuit with detergent and heat-dry after use. This will kill the stinging larvae that cause seabather's eruption.
- Talk to your doctor about carrying epinephrine if you have had any sort of allergic reaction or severe reaction to a marine sting in the past. Learn how and when to give yourself an epinephrine shot, and have it near you at all times.
- Consider using a topical jellyfish sting inhibitor lotion, such as Safe Sea.
Preparing For Your Appointment
To prepare for your appointment, see the topic Making the Most of Your Appointment.
You can help your doctor diagnose and treat your condition by being prepared to answer the following questions:
- What are your main symptoms?
- When did your symptoms begin? How have your symptoms developed, progressed, or changed since the sting?
- Do you know what you were stung by? Can you describe what stung you? Note: Bring a sample of the stinging organism with you if you can safely do so. A sample may help your doctor plan your treatment.
- When were you stung? How many times were you stung?
- Where were you when you were stung?
- Have you ever had an allergic reaction or a severe reaction to a similar sting?
- What steps have you tried at home to take care of this problem? Did they help?
- Do you have any health risks?
Current as of: July 1, 2021
Author: Healthwise Staff
William H. Blahd Jr. MD, FACEP - Emergency Medicine
Adam Husney MD - Family Medicine
Kathleen Romito MD - Family Medicine
E. Gregory Thompson MD - Internal Medicine
David Messenger MD
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