[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [Pharmacology](https://durgical.com/en/pharmacology/) › [Antivenoms](https://durgical.com/en/pharmacology/classes/antivenoms/) › Polyvalent snake antivenom (Bothrops and Crotalus) [Pharmacology](https://durgical.com/en/pharmacology/) · [Antivenoms](https://durgical.com/en/pharmacology/classes/antivenoms/) # Polyvalent snake antivenom (Bothrops and Crotalus) Horse antivenom from Colombia's INS against the venom of Bothrops (mapaná, taya equis, terciopelo) and Crotalus (rattlesnake). Given intravenously. Updated 2026-11-01 - Class: [Antivenoms](https://durgical.com/en/pharmacology/classes/antivenoms/) - Target: Toxins of Bothrops and Crotalus venoms - ATC code: J06AA03 - WHO Model List of Essential Medicines Also called: Polyvalent anti-snake antivenom, Anti-Bothrops/anti-Crotalus antivenom ◆**Toxins of Bothrops and Crotalus venoms**Polyvalent snake antivenom (Bothrops and Crotalus) ⓘ The figure shows a phospholipase A2-like myotoxin from Bothrops asper venom, one of the components the antivenom neutralises. **Target in 3D:** Toxins of Bothrops and Crotalus venoms. PDB structure 1CLP (RCSB PDB, public domain). [View the structure at RCSB PDB](https://www.rcsb.org/structure/1CLP) · Drag to rotate · pinch to zoom ## Mechanism of action It is specific equine IgG, purified from the plasma of horses immunised with Bothrops and Crotalus venoms from different regions of Colombia. The antibodies bind circulating toxins: in Bothrops, enzymes that consume clotting factors and cause bleeding, and toxins that damage local tissue; in Crotalus, neurotoxic and myotoxic phospholipases. It does not reverse tissue damage already done. - Injected venom releases enzymes and toxins into the blood - Equine IgG binds the circulating toxins - Coagulopathy is corrected and systemic damage halted - Local necrosis already established is not reversed ## Pharmacokinetics **Distribution** Intravenous; whole IgG, which stays in the plasma where clotting-disrupting toxins act ## Indications - Bothrops envenoming (mapaná, taya equis, terciopelo and related species) with local or systemic signs - Crotalus (rattlesnake) envenoming ## Adverse effects ### Common - Early reactions: urticaria, itching, fever - Pyrogenic reactions (chills and fever) during the infusion ### Serious (rare, important) - Anaphylaxis with hypotension or bronchospasm within the first hours - Serum sickness days to weeks later (fever, urticaria, joint pain, lymph-node swelling) ## Contraindications - No absolute contraindication in envenoming that needs it; a history of reaction to equine sera requires readiness to treat anaphylaxis ## Key interactions **Adrenaline (epinephrine)** The treatment for antivenom anaphylaxis; it must be available before the infusion starts ## What is monitored - Clotting tests and platelet count to judge response - Limb circumference and spread of local swelling - Kidney function and urine (myoglobinuria in Crotalus) - Continuous vital signs during the infusion ## Administration and safety - Intravenous only, under continuous medical supervision - Store refrigerated (2–8 °C) as the manufacturer states - Have adrenaline and anaphylaxis equipment ready before starting - Record the batch given and notify the case to the surveillance system ## Nursing care - Avoid unnecessary movement of the limb; no tourniquets, incisions or suction - Monitor vital signs and signs of anaphylaxis throughout the infusion - Measure limb circumference and watch for bleeding from gums, urine or puncture sites - Explain the symptoms of serum sickness that can appear weeks later ## Pregnancy and breastfeeding Severe envenoming endangers mother and fetus; pregnancy does not prevent antivenom when it is indicated. ## Memory aid "Time is tissue": the antivenom halts the mapaná's coagulopathy and the rattlesnake's neurotoxicity, but cannot bring back muscle that has already died. ## Test yourself Think of the answer, then tap the question to see it. ## Against which snake genera is the INS polyvalent antivenom indicated? Bothrops (mapaná, equis and related species) and Crotalus (rattlesnake). ## What is the INS polyvalent snake antivenom made of? Specific IgG purified from the plasma of horses immunised with Bothrops and Crotalus venoms. ## Why does antivenom not reverse established local necrosis? Antibodies neutralise free toxins; cell damage already done in tissue is not undone, which is why early treatment matters. [Add to my cards (3)](https://durgical.app/estudiar/?add=/en/pharmacology/polyvalent-snake-antivenom/) ## Related drugs - [Polyvalent coral snake antivenom (Micrurus)](https://durgical.com/en/pharmacology/polyvalent-coral-snake-antivenom/) - [Polyvalent Lonomia antivenom](https://durgical.com/en/pharmacology/polyvalent-lonomia-antivenom/) [← Back to the class: Antivenoms](https://durgical.com/en/pharmacology/classes/antivenoms/) Educational content on how drugs work; not a prescribing guide and no substitute for a health professional's advice. No doses are given. Sources: [Venta de Antivenenos](https://www.ins.gov.co/Direcciones/Produccion/Paginas/Suero-antiofidico-polivalente.aspx) (Instituto Nacional de Salud (Colombia), 2026); [Snakebite envenoming](https://www.who.int/news-room/fact-sheets/detail/snakebite-envenoming) (World Health Organization, 2026); [Guidelines for the production, control and regulation of snake antivenom immunoglobulins, Annex 5, TRS No 1004](https://www.who.int/publications/m/item/snake-antivenom-immunoglobulins-annex-5-trs-no-1004) (World Health Organization, 2017); Farmacología básica y clínica (Katzung), ch. 58 (McGraw Hill, 2025). ## **Spotted a mistake?** We are always improving for the community. Tell us what is wrong and our team will review it. Report a mistake Representative model, for educational purposes only. --- Source: https://durgical.com/en/pharmacology/polyvalent-snake-antivenom/ License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/pharmacology/polyvalent-snake-antivenom/