Bluebottles are the most common cause of jellyfish stings in Australia. Bluebottles (also known as Portugese Man-of-War jellyfish) vary in size, and the severity of the sting usually depends on the amount of contact the skin has had with the tentacle.
- A bluebottle sting usually causes an immediate and severe pain, which generally fades over about an hour.
- You can usually see where on the body the sting has occurred because there will be a red line where the tentacle has touched.
- Sometimes this line has a ‘beaded’ appearance, and is swollen and itchy.
- Occasionally blisters can develop at the site of the sting, and very rarely the sting will later cause scarring.
- It is very unlikely that someone who has been stung by a bluebottle will develop other symptoms such as abdominal pain, nausea and vomiting, although it is possible.
Treatment for bluebottle stings
- Carefully remove any remaining tentacles by gently washing the area in sea water and carefully picking off any tentacles, taking care to avoid further stings, preferably by wearing gloves.
- Washing the site of the sting with vinegar is NOT recommended for bluebottle stings.
- Immerse the area where the bluebottle sting has occurred in hot water (45 degrees Celsius – no hotter than the rescuer can comfortably tolerate) for at least 20 minutes or, if this is not possible, direct a hot shower on the area for this length of time.
- Use of hot water is more effective at reducing the pain of bluebottle stings than the previously advised use of ice packs and cold water. However, if hot water is not available a cold pack may help.
- If after this treatment there is continuing pain, itchiness or blistering at the site of the sting, it would be best to visit a doctor who might prescribe a topical treatment such as a cortisone cream to reduce the inflammatory reaction.
- In the tropical north of Australia, the first aid advice for jellyfish stings is slightly different as the box jellyfish and Irukandji jellyfish are found in these waters. Their stings can be life-threatening. Vinegar is effective at stopping the tentacles of these jellyfish releasing more venom (the opposite to the effect on bluebottles). In tropical Australia, if you cannot clearly identify a jellyfish sting as due to a harmless jellyfish or bluebottle, then it is safer to treat the sting with vinegar and to call for medical help.
When to seek medical advice
Although extremely unlikely, it is possible that a bluebottle sting may mimic anaphylaxis also known as an anaphylactic reaction (a severe allergic reaction that can be life-threatening).
- If a person who has been stung by a bluebottle develops distressing chest tightness or difficulty breathing and is getting worse, call 000 to get urgent medical help.
- If the sting area is large (e.g. affects more than half of the arm or leg) or involves a sensitive area such as the eye, seek medical help.
- In tropical Australia, if you cannot identify the jellyfish as a harmless jellyfish or bluebottle, treat with vinegar and call for medical help.
- If there is continuing pain, itchiness or blistering at the site of the sting, visit a doctor.
Last Reviewed: 05/10/2015
1. Australian Resuscitation Council. Envenomation - jellyfish stings guideline. Melbourne: ARC; Jul 2010. http://www.resus.org.au/ (accessed Sept 2015).
2. Loten C, Stokes B, Worsley D, et al. A randomised controlled trial of hot water (45C) immersion versus ice packs for pain relief in bluebottle stings. Med J Aust 2006; 184: 329-33. (accessed Sept 2015).
3. Jellyfish stings. In: eTG complete. Melbourne: Therapeutic Guidelines Limited; 2008. http://online.tg.org.au/complete/ (accessed Sept 2015).