Anti-snake venom (ASV)
Polyvalent ASV for systemic envenoming or severe local swelling: usually 10 vials IV over 1 hour; same dose for children. Adrenaline ready.
On this page
When to give
- Abnormal 20-minute whole blood clotting test or bleeding.
- Neurotoxic signs: ptosis, weakness, breathing difficulty.
- Shock, AKI, dark urine.
- Rapidly spreading local swelling (more than half the limb).
Dose
Typically 10 vials (100 mL) polyvalent ASV diluted in saline, IV over 1 hour. Children get the same dose as adults. Repeat clotting test 6 hours later; repeat doses if still abnormal. For neurotoxic bites, repeat after 1–2 hours if no improvement and give neostigmine with atropine for cobra bites.
Reactions
Common. Keep adrenaline ready: 0.5 mg IM (0.01 mg/kg in children) for anaphylaxis. Pre-medication doesn't reliably prevent reactions.
Frequently asked questions
Do children need a smaller dose of anti-snake venom?
No. The dose depends on the venom injected, not the size of the patient.
Used in these guides
Sources
Doses on this page are typical doses from the sources above. Always confirm with a current drug reference, the product leaflet and your hospital protocol, especially in children, pregnancy and kidney or liver disease.