A box jellyfish sting is a life-threatening medical emergency. In first aid, the main priorities are getting the person out of the water, calling 000, starting CPR if needed, and using vinegar in the right setting.
What is a box jellyfish sting?
A box jellyfish sting happens when tentacles from a dangerous tropical box jellyfish touch the skin and inject venom.
Box jellyfish are found mainly in tropical northern Australian waters. Their stings can cause severe pain, collapse, breathing problems, and cardiac arrest.
What symptoms can happen?
Symptoms can include:
- severe immediate pain
- long red or whip-like skin marks
- sweating
- nausea or vomiting
- collapse
- trouble breathing
- cardiac arrest
If the person is stung in tropical waters and the jellyfish type is unknown, treat it as a dangerous jellyfish sting until proven otherwise.
What should you do in first aid?
If someone may have a box jellyfish sting:
- Remove them from the water if it is safe to do so.
- Call
000immediately and ask for an ambulance. - Get help from a lifeguard if one is nearby.
- If the person is not breathing normally, start CPR straight away.
- Pour or spray vinegar onto the sting for at least 30 seconds.
- Remove tentacles after the vinegar if possible.
- Use a cold pack for pain if available.
Do not put fresh water directly on the sting.
What about Irukandji?
Some small tropical box jellyfish can cause Irukandji.
In Irukandji syndrome, the skin mark can seem minor at first, but severe symptoms may begin later. That is why delayed pain, restlessness, sweating, chest pain, or worsening illness after a tropical jellyfish sting should still be treated as an emergency.
When is it an emergency?
A suspected box jellyfish sting is always an emergency, especially if the person:
- is in tropical northern waters
- has severe pain
- collapses
- has trouble breathing
- becomes Unresponsive
People who seem stable at first can still become very unwell later, so urgent medical care is important.
How is this page different from the other jellyfish pages?
This page focuses on the dangerous tropical box-jellyfish pathway.
- Jellyfish Stings is the broader jellyfish overview page
- Irukandji covers the delayed-symptom syndrome caused by some small tropical box jellyfish
- Bluebottle Sting covers the common painful local-sting pathway
- Sea Creature Bites and Stings is the broader marine-injury overview page
Summary
A box jellyfish sting is a life-threatening emergency. Call 000, start CPR if needed, use vinegar for at least 30 seconds, remove tentacles after vinegar, and keep the person under urgent medical care.
Sources reviewed
- Healthdirect: sea creature bites and stings
- Healthdirect: jellyfish stings
- Triple Zero: official emergency calling guidance
Reviewed against Australian first aid and emergency guidance by the First Aid Glossary Editorial Team. This article is general information and does not replace emergency-operator directions, professional medical advice or hands-on first aid training.
