Stonefish Antivenom

Indication:

• Clinical evidence of systemic envenomation e.g. cardiac failure
• 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 equine sera allergy

Administration:

• Place the patient in a monitored area where anaphylaxis can be managed.
• Administer 1 ampoule for every two spine puncture wounds to a maximum of 3 ampoules undiluted by IM injection.
• Alternatively, 1 ampoule maybe 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 and systemic features. (Doses over 3 ampoules should be discussed with your toxicologist)
• Antivenom can be given as a rapid intravenous push if the patient is haemodynamically unstable or in cardiac arrest.
• 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.