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Scuba Divers and Swimmers Alert Jellyfish Stings

Scuba Diver’s and Swimmer’s Alert: Jellyfish Stings

What are jellyfish?

“Jellyfish are free-swimming, non-aggressive, gelatinous marine animals surrounded by tentacles. These tentacles are covered by sacs (nematocysts) that are filled with poison (venom) that can cause a painful to sometimes life-threatening sting. The marine animals included the “family” are jellyfish, box jellyfish (sea wasps), Portuguese man-of-war, hydroids, anemones, and fire coral. Jellyfish are found throughout the world. But, the most deadly ones are found in the Indo-Pacific and Australian waters.” (1)

For swimmers and scuba divers alike, there is growing concern about the large numbers of jellyfish inhabiting oceans and freshwater lakes, all around the world. It has been suggested that the greenhouse effect, created by the burning of fossil fuels, is contributing to an imbalance in the ecosystem that is encouraging the overgrowth of jellyfish.

Normally, fresh water jellyfish are not harmful to human beings, but in the ocean, intensely painful stings by jellyfish, can lead to anaphylaxis and immediate death. Thus immediate, medical treatment is recommended.

First aid measures or professional medical treatment for jellyfish stings should include the following measures:

The person who has been stung by a jellyfish must get out of the water immediately, or be assisted to do so, by someone who is able to help him or her. Note that jellyfish in the water, always present a hazard for rescuers and thus protective suits and gloves must be worn for any rescue attempt.

If necessary, CPR should be administered to the patient immediately.

Nematocysts or jellyfish tentacles, may still be clinging to the skin and should be washed off as soon as possible, with salt water or removed immediately with gloves or tweezers. If necessary, a knife or the sharp edge of a razor blade may be used to scrape the remaining tentacles off the skin. Never touch the tentacles with your hands, as you may be stung too.

The jellyfish sting will cause intense pain and itching and become what appears to be a skin rash with raised welts.

Vinegar (3-10 % acetic acid) should be applied directly to the sting area, but caution must be taken, so that it does not get into the patient’s eyes.

Do not rub the area of the sting with a towel or clothing, as more toxins may be ‘fired’ or released. Applying fresh water, alcohol or ammonia may also cause more toxins to be released.

Epinephrine or adrenaline may be given via an epi-pen injection.

Antihistamines, like benadryl (diphenhydramine), can be administered to relieve itching of the skin. Topical steroids or oral steroids may be prescribed.

A paste made of baking soda and water, may be applied every 15-20 minutes to reduce itching.

Ibuprofen (Motrin), Aleve and acetaminophen (Tylenol) may be administered for pain relief. The intense pain will last for approximately half an hour.

Measures to decrease the spread of the alkali-based venom, may include the use of ice or a pressure bandage. Restricted movement will also reduce the flow of venom in the body.

Watch for symptoms of abnormal heart rhythm, lowered BP, nausea, vomiting, faintness, confusion, chest pain, weakness and swelling. Numbness, tingling and muscle spasm may be evident, depending upon the location of the sting. With facial stings, the patient may experience swelling of the lips and tongue. He or she may also experience abdominal pain, accompanied by diarrhea. Swelling of the lymph nodes may occur.

For severe symptoms, like difficulty breathing or loss of consciousness, call 911, in order to obtain immediate medical advice and assistance.

For more information on the treatment of jellyfish stings, please see the following websites:






Learning how to treat jellyfish stings could save your life and that of others! Scuba divers and swimmers, always be alert to the presence of dangerous jellyfish!

(1) http://www/emedicinehealth.com/jellyfish_stings/article_em.htm