Bites & stings
Jellyfish and Marine Stings
For a jellyfish sting, rinse with seawater, remove tentacles carefully and soak in hot water; for a weever fish sting, soak the area in water as hot as tolerable.
When to call 999. Call 999 for any sign of a severe reaction — difficulty breathing, swelling of the face or throat, chest pain or collapse — for stings to the mouth or throat, or for stings from dangerous species abroad. Most UK stings, though, are painful rather than serious.
What to do
- Get the person out of the water and keep them calm and still.
- For a jellyfish sting, rinse the area with seawater (not fresh water) and remove any tentacles with tweezers or a gloved hand — do not use bare fingers.
- Soak the area, or apply a heat pack, in water as hot as can be tolerated (about 40–45°C) for at least 30 minutes to ease pain.
- For a weever fish sting (common on UK beaches), soak the affected foot in water as hot as tolerable to break down the venom.
- Take pain relief such as paracetamol if needed.
- Watch closely for any signs of a severe allergic reaction.
Avoid
What not to do
Do not rinse a jellyfish sting with fresh water or rub the area, and avoid old remedies like urine or vinegar for UK jellyfish, as these can make some stings worse. Do not touch tentacles with bare hands.
Afterwards and while you wait
Most UK jellyfish and weever fish stings settle with hot-water treatment and pain relief. Watch for signs of infection, or of an allergic reaction, and seek medical help if pain is severe or a barb or spine remains in the skin. Stings from dangerous species abroad need urgent medical care.
Education and reference only. This is general first-aid information aligned with UK guidance, not a substitute for a hands-on first-aid course or professional emergency care. In a life-threatening emergency, call 999 straight away.
Answers
Jellyfish and Marine Stings: frequently asked questions
Does hot water really help a jellyfish or weever sting?
Yes. Soaking the area in water as hot as can be tolerated (around 40–45°C) for at least 30 minutes helps break down the venom and relieve pain, and is the recommended treatment for these stings.
Should I put vinegar or urine on a jellyfish sting?
For UK jellyfish, no — these old remedies are not recommended and can worsen some stings. Rinse with seawater, remove tentacles carefully, and use hot water. Advice differs for certain tropical species, so follow local guidance abroad.
Related
Other bites & stings first aid
Sources
Where this is drawn from
- NHS — first aid
- St John Ambulance / British Red Cross first-aid guidance
- UK Health Security Agency (where relevant)
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