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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
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 (antivenin) exists.
If you get this antivenin, 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.
(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.
Based on your answers, the problem may not improve without medical
Based on your answers, you may need care right away. The problem is likely to get worse without medical care.
Based on your answers, you may need care soon. The
problem probably will not get better without medical care.
Based on your answers, you need
Call911or other emergency services now.
Shock is a life-threatening condition that may occur quickly
after a sudden illness or injury.
Symptoms of shock in a child may include:
Shock is a life-threatening condition that may quickly occur
after a sudden illness or injury.
Symptoms of shock (most of which will be present) include:
You may need a tetanus shot depending
on how dirty the wound is and how long it has been since your last shot.
Symptoms of a severe allergic reaction
(anaphylaxis) may include:
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.
Symptoms of difficulty breathing can range from mild to severe. For example:
Symptoms of infection may
Many things can affect how your body responds to a symptom and what kind
of care you may need. These include:
Pain in adults and older children
You have answered all the questions. Based on your answers, you may be
able to take care of this problem at home.
Pain in children under 3 years
It can be hard to tell how much pain a baby or toddler is in.
Certain health conditions and medicines weaken the immune system's ability to fight off infection and
illness. Some examples in adults are:
Home treatment can help ease your
discomfort and prevent other problems.
Most minor coral scrapes or
cuts can be treated at home.
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.
Call your doctor if any of the following occur during home
You can limit your risk of being injured
by jellyfish, a Portuguese man-of-war, or coral.
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
Current as of:
June 4, 2014
William H. Blahd, Jr., MD, FACEP - Emergency Medicine & David Messenger, MD
How this information was developed to help you make better health decisions.
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