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Symptoms and Signs of Jellyfish Stings Reaction, Symptoms, Pictures, and Treat

Doctor's Notes on Jellyfish Stings Reaction, Symptoms, Pictures, and Treat

Jellyfish are free – swimming gelatinous marine animals with tentacles containing stinging structures. Signs and symptoms of jellyfish stings are usually an intense, immediate stinging pain, itching rash and skin welts. Some jellyfish stings may have progressively worse symptoms that include nausea, vomiting, diarrhea, lymph node swelling, abdominal pain, numbness and tingling and/or muscle spasms. In addition, severe reactions to the sting include difficulty breathing, coma and even death.

Jellyfish stings are caused by stinging cells (termed nematocysts) in the tentacles. On contact with skin or other substances, a toxin or venom coated thread is injected and causes the signs and symptoms. With over 200 types of jellyfish, it is no surprise that signs and symptoms vary somewhat according to the type of jellyfish. For example, a box jellyfish sting can cause death in minutes while a small common jellyfish may produce a mild stinging pain.

Medical Author:
Medically Reviewed on 3/11/2019


Kasper, D.L., et al., eds. Harrison's Principles of Internal Medicine, 19th Ed. United States: McGraw-Hill Education, 2015.