The common opinion:
Google Health says:
For other jellyfish stings, soak or rinse the area in vinegar (acetic acid) for 15-30 minutes to stop the nematocysts from releasing their toxins. If you do not have vinegar available, rinse in sea water,70% isopropyl alcohol, or Safe Sea Jellyfish After Sting® pain relief gel. Do not use fresh water.
The ‘vinegar myth’ is false. Instead, apply CPR to the victim, and get medical attention IMMEDIATELY.
eMedicine Health has an article about jellyfish sting symptoms:
Jellyfish Sting Symptoms
- Symptoms include an intense, stinging pain, itching, rash, and raised welts.
- The progressive effects of a jellyfish sting may include nausea, vomiting, diarrhea, lymph node swelling, abdominal pain, numbness/tingling, and muscle spasms.
- Severe reactions can cause difficulty breathing, coma, and death.
- A sting from a box jellyfish or other venomous types of jellyfish can cause death in minutes.
eMedicine Health also has an article about when to seek medical care:
When to Seek Medical Care
Seek immediate medical treatment if the person stung has:
- Difficulty breathing, difficulty swallowing, chest pain, or intense pain at the site of the sting.
- If the person has been stung in the mouth or placed tentacles in their mouth and are having voice changes, difficulty swallowing, or swelling of the tongue or lips.
- If the sting happened to someone who is very young or old.
- If the sting involves a large area of the body, the face, or genitals.
- If the patient continues to have itching, redness, pain, and swelling of the skin around the sting, see a doctor.
The doctor may prescribe:
- diphenhydramine (Benadryl) to help with the itching,
- pain medication for pain, and/or
- topical steroids or steroids by mouth to help with the swelling and itching.
- The doctor may also prescribe antibiotics if the patient has cellulitis. Take all medications as directed and until they are gone.
- If it has been longer than 10 years since the patient’s last tetanus shot, a booster shot might be recommended.
Beware of jellyfish!