Lifestyle and home remedies

The best treatment for you may depend on the type of jellyfish that stung you. But most stings can be treated with these simple remedies:

• Remove stingers. Remove any pieces of jellyfish tentacle in your skin by rinsing the wound with seawater. You can also try gently scraping off the stingers with the edge of an ID card or a credit card. Avoid getting sand on the wound. And don't rinse with fresh water or rub the area with a towel, as these actions may activate more stingers.
• Rinse with vinegar or apply a baking soda paste. Rinse the affected area with vinegar for about 30 seconds. Or apply a paste of baking soda and seawater. Each method may deactivate the stingers of some types of jellyfish.
• Take a hot shower or apply ice packs. Hot water — as hot as you can tolerate but not above 113 F (45 C) — and ice packs may help ease pain.
• Take a pain reliever and apply lotions. Apply calamine lotion or lidocaine to help relieve itching and discomfort.

Source

Other medical treatments

Other circumstances also may require doctor-supervised treatment:

• A rash or other skin reaction due to delayed hypersensitivity may be treated with oral antihistamines or corticosteroids.
• A jellyfish sting occurring on or near an eye requires immediate medical care for pain control and a good eye flushing. You will likely be seen by a doctor specializing in eye care (ophthalmologist).

Source

Treatments and drugs after jellyfish attack

Most jellyfish stings can be treated by rinsing the area with salt water, applying vinegar or a baking soda paste, and taking a pain reliever.

Someone having a severe reaction to a jellyfish sting needs emergency care that may include:

• Cardiopulmonary resuscitation (CPR)
• Life support to stabilize breathing, heart rate and blood pressure
• Antivenin medication, if the sting is from a box jellyfish
• Pain medicine

Source

Complications at jellyfish stings

Possible complications of a jellyfish sting include:

• Delayed hypersensitivity reaction, causing blisters, rash or other skin irritations a week or more after the sting
• Severe allergic reaction (anaphylaxis), rarely
• Infection, rarely
• Scarring or skin discoloration, rarely

Source

Risk factors Jellyfish stings

Conditions that increase your risk of getting stung by jellyfish include:

• Swimming on a downwind shore
• Swimming at times when jellyfish appear in large numbers (a jellyfish bloom)
• Swimming or diving in jellyfish areas without protective clothing
• Playing or sunbathing where jellyfish are washed up on the beach
• Swimming in a place known to have many jellyfish

Source

Causes stings

Jellyfish tentacles contain microscopic barbed stingers. Each stinger has a tiny bulb that holds venom and a coiled, sharp-tipped tube. The jellyfish uses the venom to protect itself and kill prey.

When you brush against a tentacle, tiny triggers on its surface release the stingers. The tube penetrates the skin and releases venom. It affects the immediate area of contact and may enter the bloodstream.

So, can do jellyfish sting when it is dead ? Yes, jellyfish that has washed up on a beach may still release venomous stingers if touched.

Types of jellyfish

While many types of jellyfish are relatively harmless to humans, some can cause severe pain and are more likely to cause a systemic reaction. These jellyfish cause more-serious problems in people:

Box jellyfish. 
Also called sea wasps, box jellyfish can cause intense pain. Life-threatening reactions — although rare — are more common with this type. The more dangerous species of box jellyfish are in the warm waters of the Pacific and Indian oceans.

Portuguese man-of-war.
 Also called bluebottle jellyfish, Portuguese man-of-war jellyfish live mostly in warmer seas. This type has a blue or purplish gas-filled bubble that keeps it afloat on the water and acts as a sail.

Sea nettle. 
Common in both warm and cool seawaters, sea nettles live along the northeast coast of the United States and are abundant in Chesapeake Bay.

Lion's mane jellyfish. 
These are the world's largest jellyfish, with a body diameter of more than 3 feet (1 meter). They're most common in cooler, northern regions of the Pacific and Atlantic oceans.

Source

Signs of jellyfish stings

Common signs and symptoms of jellyfish stings include:

• Burning, prickling, stinging pain
• Red, brown or purplish tracks on the skin — a "print" of the tentacles' contact with your skin
• Itching
• Swelling
• Tingling and numbness
• Throbbing pain that radiates up a leg or an arm

Severe jellyfish stings can affect multiple body systems. These reactions may appear rapidly or several hours after the stings. Signs and symptoms of severe jellyfish stings include:

• Nausea and vomiting
• Headache
• Muscle and joint problems
• Weakness and dizziness
• Fever
• Loss of consciousness
• Difficulty breathing
• Heart problems

The severity of your reaction depends on:

• The type and size of the jellyfish
• Your age, size and health, with severe reactions more likely in children and people in poor health
• How long you were exposed to the stingers
• How much of your skin is affected
• When to see a doctor

Seek emergency treatment if:

• Sting's cover large areas of skin
• You have severe symptoms or a serious allergic reaction

Source