- Clinical evidence of envenomation
- Laboratory evidence of anticoagulant coagulopathy
- Laboratory evidence of myotoxicity CK >1000 IU/L
- No absolute
- Increased Risk of anaphylaxis in patients previously treated with antivenom or those who are suspected of equine sera allergy
- Place the patient in a monitored area where anaphylaxis can be managed
- Administer 1 ampoule diluted in 500ml of 0.9% saline IV over 20 minutes (the dose is the same for adults and paediatrics – snakes don’t envenomate less because its a child)
- Re-check coagulation profile and CK 12 hours after antivenom administration
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.
- If black snake antivenom is not readily available one ampoule of Polyvalent Snake Antivenom may be used – however, there is an increased risk of anaphylaxis
- Tiger Snake Antivenom is an alternative to Black Snake Antivenom for those patients envenomed by the red-bellied or blue-bellied black snake
- Churchman A, O’Leary MA, Buckley NA et al. Clinical effects of red-bellied black snake (Pseudechis porphyriacus) envenoming and correlation with venom concentrations: Australian Snakebite Project (ASP-11). Medical Journal of Australia 2010;193:696-700
- Johnston CI, Brown SGA, O’Leary MA et al. Mulga snake (Pseudechis australis) envenoming: a spectrum of myotoxicity, anticoagulant coagulopathy, haemolysis and the role of early antivenom therapy – Australian Snakebite Project (ASP-19). Clinical Toxicology 2013; 51:417-424
- White J. A clinician’s guide to Australian venomous bites and stings: Incorporating the updated CSL antivenom handbook. Melbourne: CSL Ltd, 2012.