Jellyfish stings are a common nuisance to swimmers and divers. With trailing tentacles that contain thousands of tiny barbed stingers, jellyfish are found in all of the world's oceans. Jellyfish stings range from mild to severe. Some jellyfish are very poisonous and even small stings can cause severe pain and irritation, while other jellyfish are harmless to humans. Most jellyfish stings get better with home treatment, but some types of jellyfish stings can be more severe and require medical treatment. In rare cases, jellyfish stings that are widespread or from certain species of jellyfish can be life-threatening.
What causes Jellyfish?
Jellyfish tentacles contain tiny, poisonous barbs that are released when they come in contact with something. These poisonous barbs, known as nematocysts, are used by the jellyfish to immobilize prey such as small fish. When a person brushes against jellyfish tentacles, it causes the nematocysts to inject poison into the surface of the person's skin.
Some jellyfish are harmless, but a number of jellyfish can cause painful stings. Certain jellyfish are very poisonous and cause severe stings. Some jellyfish that can cause painful or severe stings include:
The Portuguese man-of-war. Also called a bluebottle jellyfish, has a distinctive purple bubble on top that acts as a sail. It's commonly found on the east and west coasts of North America, in Hawaii and in the Gulf of Mexico.
The sea nettle. This jellyfish may be brown or red and is common off the Atlantic coast of the United States. Sea nettles are often found in large groups or washed up on shore. They are common in the Chesapeake Bay.
The box jellyfish. Also known as the sea wasp, this is one of the world's most poisonous creatures. It's found in the world's warmer oceans. One particularly dangerous type of box jellyfish, the tiny Irukandji, is found on the east coast of Australia. Its sting can cause excruciating pain and a severe, life-threatening reaction known as Irukandji syndrome.
The lion's mane. This is the world's largest jellyfish. It can reach a diameter of 8 feet (2.4 meters) across. It's most common in cooler, northern regions of the Pacific and Atlantic oceans.
Treatment of Jellyfish
Most jellyfish stings can be treated with home remedies. Steps include:
Deactivating stingers. Wash off the sting area immediately with seawater to remove any remaining tentacles. Be sure to use seawater; using fresh water can cause more stings to occur. Then, rinse the sting area with vinegar to neutralize stingers still on the skin. Don't use vinegar for Chesapeake Bay sea nettle stings.
Removing any remaining stingers. Remove leftover stingers by applying shaving cream or a paste of seawater and baking soda or sea water and talcum powder to the sting area. Scrape it off when it dries.
Relieving pain. Ice and over-the-counter skin creams (such as calamine lotion) can help with pain and itching. Rinsing or soaking the sting area with hot water may also help.
For severe stings, home remedies may not be enough, and medical attention or emergency treatment may be needed. Emergency treatment can include:
Resuscitation. In very rare cases, severe, widespread jellyfish stings can cause heart failure (cardiac arrest) and immediate CPR is needed.
Life support. If you have a serious reaction that affects body functions and not just your skin (systemic reaction), the first priority in emergency treatment is to stabilize your breathing, heart rate, blood pressure, and other vital functions.
Antivenom. If the sting is caused by a box jellyfish, you may need an immediate dose of antivenom to counter the effects of the jellyfish poison in your system.
Pain control. In most cases, pain caused by bad jellyfish stings can be treated with skin creams. If the pain is severe or you're having muscle spasms, you may need (IV) or injected pain medications or other medications.
If you do need emergency treatment for a systemic reaction caused by severe jellyfish stings, you'll need to stay in the hospital for at least 6 to 8 hours.
