Jellyfish stings

Jellyfish stings are relatively common problems for people swimming, wading or diving in seawaters. The long tentacles trailing from the jellyfish body can inject you with venom from thousands of microscopic barbed stingers.

Jellyfish stings vary greatly in severity. Most often they result in immediate pain and red, irritated marks on the skin. Some jellyfish stings may cause more whole-body (systemic) illness. And in rare cases jellyfish stings are life-threatening.

Most jellyfish stings get better with home treatment. Severe reactions require emergency medical care.

Symptoms Causes Risk factors Complications Prevention

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:

  • Stings cover large areas of skin
  • You have severe symptoms or a serious allergic reaction

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