Funnel Web Antivenom
Liverpool Hospital Emergency Department
Indications:
- Suspected funnel web spider envenoming and signs of severe envenoming
- Cholinergic and adrenergic features
- (sweating, salivation, lacrimation, piloerection, hypertension etc.)
- Paraesthesia / fasciculations / spasms
- Myocardial dysfunction and dysrhythmia
- Pulmonary oedema
- Agitation anxiety and coma
- Abdominal pain nausea and vomiting
(Have to hand in any BIG BLACK SPIDER BITE!!!!!!)
Formulation: Stock 2
- 125 units of funnel web spider antivenom each vial
Dosage and Administration
- Administer in a critical care area with access to adrenaline and resuscitation equipment
- Recommended dose is 2 vials of Funnel Web antivenom (dose the same for both adults and children)
- Dilute in 1:10 NaCl 0.9% or Hartmanns or 1:5 if at risk of fluid overload or paediatric cases
- Gently swirl or invert to completely dissolve, it may take up to 10 minutes to achieve colourless solution.
- Administer by slow IV injection
- Can also be given undiluted as IV slow push over 2 minutes
- Generally additional doses are not required however discuss with a clinical toxicologist in particular if inadequate response
- Can be given in paediatrics or pregnancy
Side Effects
- Anaphylaxis
- If there is an acute allergic or anaphylactic reaction temporarily stop the infusion and treat accordingly then recommence the infusion at a slower rate.
- Rarely adrenaline infusion may be needed to complete the full dosage of antivenom
- Delayed serum sickness; fever, rash, arthralgia and myalgia
- Lymphadenopathy, albuminuria, arthritis, nephritis and vasculitis
Pit Falls
- Severe funnel web envenoming may develop catechol related myocardial dysfunction requiring inotropic support – consult Clinical Toxicologist
- Admit all patients who have required antivenom and monitor for 12-24 hours until envenoming has resolved
- Warn re serum sickness when discharging