Brown Snake Antivenom

Liverpool Hospital Emergency Department


  • Brown Snake envenoming
  • Unidentified snake envenoming and no requirement for polyvalent antivenom given in  combination with tiger snake antivenom 

Formulation: Stock 1 

  • 1000 units of Brown Snake antivenom each vial 

Dosage and Administration 

  • Brown Snake Envenoming (indicated if there is expert identification or the snake, discussion with  a clinical toxicologist or poisons information centre)
    • 1 vial brown snake antivenom diluted 1:10 0.9% NaCl or Hartmanns IV over 15 minutes. 
    • If at risk of fluid overload or paediatric case dilute in a 1:5 ratio 
  • Unidentified snake envenoming
    • 1 vial brown snake antivenom & 1 vial tiger snake antivenom diluted 1:10 in NaCl 0.9%  or Hartmanns. Give IV over 15 – 20 minutes
    • In children or those with risk of fluid overload dilute 1:5. 
  • In life-threatening emergency situations antivenom can be given undiluted as a rapid injection.
  • Administer in a critical care area with readily available adrenaline and resuscitation equipment

Side Effects 

  • Immune mediated hypersensitivity reactions occur in 25% of cases with urticaria / rash
  • Anaphylaxis occurs in 2-3% of patients and manifests as hypotension
  • If there is an acute allergic or anaphylactic reaction temporarily stop the infusion and  treat accordingly then recommence the infusion at a slower rate.
  • IgE mediated reactions occur generally in snake handlers who have had prior venom  exposure and anaphylaxis to venom


  • Treat hypersensitivity by ceasing the antivenom temporarily
    • Administer IM adrenaline if severe (adult 500mcg 1:1000 IM / paediatric 10microgram/kg IM) 
  • Delayed serum sickness;
    • fever, rash, arthralgia and myalgia:
    • Moderate to severe serum sickness  can be treated with prednisolone
  • There is no role for premedication in Australian snake bites 

Pit Falls: 

  • DO NOT WITHHOLD ANTIVENOM in cases of snake handlers who have venom associated  anaphylaxis
  • One vial of each of tiger snake and brown snake monovalent antivenom covers most unidentified  snake bites in SWSLHD including red bellied black snake envenoming
  • Recovery can be difficult to assess and is based on reversibility of the venom effects and time for  the body to recover post venom neutralisation
  • Systemic effects such as VICC are irreversible and venom only prevents this if given early – will  take 24-36 hours to resolve
  • Clotting times will only normalise after a few days
  • Discuss major bleeding with clinical toxicologist re role of clotting factor replacement and surgical  intervention
  • Discharge after resolution of symptoms / no evidence of thrombotic microangiopathy and kidney  injury / normal INR / decreasing CK
  • All antivenom can be given in pregnancy
  • Warn re serum sickness when discharging