Box Jellyfish Antivenom

Box Jellyfish Antivenom (ovine IgG Fab) can be used to treat envenomation from box jellyfish found in Australian Waters.

Indication:

• Clinical evidence of systemic envenomation e.g. cardiovascular compromise or cardiac arrest
• Severe localised pain unrelieved by intravenous opiates

Contraindication:

• No absolute
• Increased Risk of anaphylaxis in patients previously treated with antivenom or those who are suspected of ovine sera allergy

Administration:

• Place the patient in a monitored area where anaphylaxis can be managed.
• 1 ampoule diluted in 100ml of 0.9% saline and administered intravenous over 20 minutes.
• Repeat doses maybe given one ampoule at a time until resolution of local or systemic features. (Doses over 3 ampoules should be discussed with your toxicologist)
• For patients with haemodynamic compromise 3 ampoules are given in 100ml of 0.9% saline over 20 minutes. This maybe repeated again until the patient is stable.
• Antivenom can be given as a rapid intravenous push if the patient is in cardiac arrest give up to 6 ampoules in this case.
• Adult and paediatric doses are the same.

Adverse drug reactions:

• Anaphylaxis: Cease antivenom infusion, treat as per anaphylaxis with oxygen, IV fluids and IM adrenaline. Recommence antivenom infusion when anaphylaxis has resolved. Rarely will ongoing administration of adrenaline be required to complete the antivenom infusion.
• Serum Sickness: A benign and self limiting complication occurs 5-10 days after antivenom, symptoms include fever, rash, arthralgia and myalgia. Oral steroids for 5 days may ameliorate symptoms (e.g. prednisolone 50mg/day in adults and 1mg/kg in children). All patients should be warned about this complication who receive antivenom.

Top tips and Controversies:

• Most patients only require ice and simple analgesia for box jellyfish stings
• The box jellyfish antivenom is ineffective against other jellyfish stings including irukandji syndrome
• Anecdotally antivenom works as an analgesic but this has not been reproduced in clinical trials
• In vitro the antivenom binds well to the venom but in vivo it does not appear to prevent a venom-induced cardiovascular collapse and therefore its clinical value is debated

References

• Currie BJ. Marine antivenoms. Journal of Toxicology Clinical Toxicology 2003; 41:301-308.
• White J. A clinician’s guide to Australian venomous bites and stings: Incorporating the updated CSL antivenom handbook. Melbourne: CSL Ltd, 2012.
• Winter KL, Isbister GK, Jacoby T et al.  An in vivo comparison of the efficacy of CSL box jellyfish antivenom with antibodies raised against nematocyst-derived Chironex fleckeri venom.  Toxicology Letters 2009;187:94-98.