Antivenom, also known as antivenin, venom antiserum, and antivenom immunoglobulin, is a specific treatment for envenomation. It is composed of antibodies and used to treat certain venomous bites and stings.[1] Antivenoms are recommended only if there is significant toxicity or a high risk of toxicity.[1] The specific antivenom needed depends on the species involved.[1] It is given by injection.[1]

Antivenom
Milking a snake for the production of antivenom
Clinical data
Other namesantivenin, antivenene
AHFS/Drugs.comMonograph
Routes of
administration
injection
ATC code
Identifiers
ChemSpider
  • none

Side effects may be severe.[1] They include serum sickness, shortness of breath, and allergic reactions including anaphylaxis.[1] Antivenom is traditionally made by collecting venom from the relevant animal and injecting small amounts of it into a domestic animal.[2] The antibodies that form are then collected from the domestic animal's blood and purified.[2]

Versions are available for spider bites, snake bites, fish stings, and scorpion stings.[3] Due to the high cost of producing antibody-based antivenoms and their short shelf lives when not refrigerated, alternative methods of production of antivenoms are being actively explored.[4] One such different method of production involves production from bacteria.[5] Another approach is to develop targeted drugs (which, unlike antibodies, are usually synthetic and easier to manufacture at scale).[6]

Antivenom was first developed in the late 19th century and came into common use in the 1950s.[2][7] It is on the World Health Organization's List of Essential Medicines.[8]

Medical uses edit

Antivenom is used to treat certain venomous bites and stings.[1] They are recommended only if there is significant toxicity or a high risk of toxicity.[1] The specific antivenom needed depends on the venomous species involved.[1]

In the US, approved antivenom, including for pit viper (rattlesnake, copperhead and water moccasin) snakebite, is based on a purified product made in sheep known as CroFab.[9] It was approved by the FDA in October 2000. U.S. coral snake antivenom is no longer manufactured, and remaining stocks of in-date antivenom for coral snakebite expired in fall 2009, leaving the U.S. without a coral snake antivenom. Efforts are being made to obtain approval for a coral snake antivenom produced in Mexico which would work against U.S. coral snakebite, but such approval remains speculative.[10][11]

As an alternative when conventional antivenom is not available, hospitals sometimes use an intravenous version of the antiparalytic drug neostigmine to delay the effects of neurotoxic envenomation through snakebite.[12] Some promising research results have also been reported for administering the drug nasally as a "universal antivenom" for neurotoxic snakebite treatment.[13]

A monovalent antivenom is specific for one toxin or species, while a polyvalent one is effective against multiple toxins or species.[14]

The majority of antivenoms (including all snake antivenoms) are administered intravenously; however, stonefish and redback spider antivenoms are given intramuscularly. The intramuscular route has been questioned in some situations as not uniformly effective.[15]

Antivenoms bind to and neutralize the venom, halting further damage, but do not reverse damage already done. Thus, they should be given as soon as possible after the venom has been injected, but are of some benefit as long as venom is present in the body. Since the advent of antivenoms, some bites which were previously invariably fatal have become only rarely fatal provided that the antivenom is given soon enough.[citation needed]

Side effects edit

Antivenoms are purified from animal serum by several processes and may contain other serum proteins that can act as immunogens. Some individuals may react to the antivenom with an immediate hypersensitivity reaction (anaphylaxis) or a delayed hypersensitivity (serum sickness) reaction, and antivenom should, therefore, be used with caution. Although rare, severe hypersensitivity reactions including anaphylaxis to antivenom are possible.[16] Despite this caution, antivenom is typically the sole effective treatment for a life-threatening condition, and once the precautions for managing these reactions are in place, an anaphylactoid reaction is not grounds to refuse to give antivenom if otherwise indicated. Although it is a popular myth that a person allergic to horses "cannot" be given antivenom, the side effects are manageable, and antivenom should be given rapidly as the side effects can be managed.[17]

Method of preparation edit

Most antivenoms are prepared by freeze drying (synonym, cryodesiccation, lyophilization). The process involves freezing the antisera, followed by application of high vacuum. This causes frozen water to sublimate. Sera is reduced to powder with no water content. In such an environment, microorganisms and enzymes cannot degrade the antivenom, and it can be stored for up to 5 years [at normal temperatures]. Liquid antivenoms may also be stored for 5 years, but they must be stored at low temperatures [<8 degrees Celsius (or 46 degrees Fahrenheit)].[18]

Mechanism edit

Antivenoms act by binding to and neutralizing venoms. The principle of antivenom is based on that of vaccines, developed by Edward Jenner; however, instead of inducing immunity in the person directly, it is induced in a host animal and the hyperimmunized serum is transfused into the person.[19] The host animals may include horses, donkeys, goats, sheep, rabbits, chickens, llamas, and camels.[20] In addition, opossums are being studied for antivenom production.[21] Antivenoms for medical use are often preserved as freeze-dried ampoules, but some are available only in liquid form and must be kept refrigerated. They are not immediately inactivated by heat, however, so a minor gap in the cold chain is not disastrous.

History edit

The use of serum from immunized animals as a treatment for disease was pioneered in 1890 by Emil von Behring and Shibasaburo Kitasato, who first demonstrated that the infectious diseases diphtheria and tetanus could be prevented or cured using transfusions from an immune animal to a susceptible one.[22] On February 10, 1894, Albert Calmette at the Pasteur Institute, and independently Césaire Auguste Phisalix and Gabriel Bertrand at the National Museum of National History in France, announced that they had achieved the same result—treatment of a vulnerable animal with serum from an immunized one—this time using snake venom as the source of protection and disease.[23] Calmette went on subsequently to immunize horses using venom from Indian cobras, and the resulting Serum Antivenimeux (antivenomous serum) became the first commercially-available antivenom product.[24][25]

Natural immunity of snakes to their own venom was observed at least as long ago as 1767, by Felice Fontana in his work Ricerche Fisiche sopra il Veleno della Vipera (Physical Research on the Venom of the Viper).[26] Surgeon-Major Edward Nicholson wrote in the November 1870 Madras Medical Journal that he had witnessed a Burmese snake-catcher inoculating himself with cobra venom. However, the snake-catcher was unsure whether this was actually effective and therefore continued to treat his snakes with care. Nicholson, along with other Britons, began to consider that venom might provide its own cure. Although Scottish surgeon Patrick Russell had noted in the late 18th century that snakes were not affected by their own venom,[27] it was not until the late 19th century that Joseph Fayrer, Lawrence Waddell, and others began to consider venom-based remedies again. However, they and other naturalists working in India did not have the funding to fully develop their theories. In 1895 Sir Thomas Fraser, Professor of Medicine at the University of Edinburgh, picked up Fayrer and Waddell's research to produce a serum to act against cobra venom. His "antivenene" was effective in the laboratory, but failed to make an impact as the public were focused on contemporary Pasteurian discoveries.[28]

In 1901, Vital Brazil, working at the Instituto Butantan in São Paulo, Brazil, developed the first monovalent and polyvalent antivenoms for Central and South American Crotalus and Bothrops genera,[29] as well as for certain species of venomous spiders, scorpions, and frogs. In Mexico in 1905, Daniel Vergara Lope developed an antivenom against scorpion venom, by immunizing dogs.[30] In Australia, the Commonwealth Serum Laboratories (CSL) began antivenom research in the 1920s. CSL has developed antivenoms for the redback spider, funnel-web spiders and all deadly Australian snakes.[31] In the USA, the H.K. Mulford company began producing "Nearctic Crotalidae antivenin"[32] in 1927, via a consortium called the Antivenin Institute of America.[33]

Over time, a variety of improvements have been made in the specificity, potency, and purity of antivenom products, including "salting out" with ammonium sulphate or caprylic acid,[34] enzymatic reduction of antibodies with papain or with pepsin, affinity purification, and a variety of other measures.[35] Many equine facilities now use plasmapheresis to collect blood plasma instead of blood serum.[36][37]

Availability edit

There is an overall shortage of antivenom to treat snakebites. Because of this shortage, clinical researchers are considering whether lower doses may be as effective as higher doses in severe neurotoxic snake envenoming.[38]

Antivenom undergoes successive price markups after manufacturing, by licencees, wholesalers and hospitals.[39] When weighed against profitability (especially for sale in poorer regions), the result is that many snake antivenoms, world-wide, are very expensive. Availability, from region to region, also varies.[40]

Internationally, antivenoms must conform to the standards of pharmacopoeia and the World Health Organization (WHO).[20][41]

In 2024 researchers have discovered a synthetic antibody that can neutralize a key type of neurotoxin produced by four different deadly snake species from South Asia, Southeast Asia, and Africa. This might be a step toward an antivenom that could be used on any of the 200 or so dangerous venomous snakes throughout the world.[42]

Antivenoms have been developed for the venoms associated with the following animals:[43]

Spiders edit

Antivenom Species Country
Funnel web spider antivenom Sydney funnel-web spider Australia
Soro antiaracnidico Brazilian wandering spider Brazil
Soro antiloxoscelico Recluse spider Brazil
Suero antiloxoscelico Chilean recluse Chile
Aracmyn All species of Loxosceles and Latrodectus Mexico
Redback spider antivenom Redback spider Australia
Black widow spider (Latrodectus Mactans) antivenin (equine origin) Southern black widow spider United States
SAIMR spider antivenom Button spider South Africa
Anti-Latrodectus antivenom Black widow spider Argentina

Acarids edit

Antivenom Species Country
Tick antivenom Paralysis tick Australia

Insects edit

Antivenom Species Country
soro antilonomico Lonomia obliqua caterpillar Brazil

Scorpions edit

Antivenom Species Country
Scorpion Venom Anti Serum (India) Purified lyophilized enzyme refined Equine Immunoglobulins Buthus tamulus India
ANTISCORP - Premium (Scorpion Venom Antiserum North Africa) Purified lyophilized enzyme refined Equine Immunoglobulins Androctonus amoerexi and Leiurus quinquestraiatus India
INOSCORPI MENA (Middle East and North Africa) Androctonus australis, Androctonus mauritanicus, Androctonus crassicauda, Buthus occitanus mardochei, Buthus occitanus occitanus, Leiurus quinquestriatus quinquestriatus, Leiurus quinquestriatus hebreus Spain
Alacramyn Centruroides limpidus, C. noxius, C. suffusus Mexico
Suero Antialacran Centruroides limpidus, C. noxius, C. suffusus Mexico
Tunisian polyvalent antivenom All Iranian scorpions Tunisia
Anti-Scorpion Venom Serum I.P. (AScVS) Indian red scorpion India
Anti-scorpionique Androctonus spp., Buthus spp. Algeria
Scorpion antivenom Black scorpion, Buthus occitanus Morocco
Soro antiscorpionico Tityus spp. Brazil
SAIMR scorpion antivenin Parabuthus spp. South Africa
Purified prevalent Anti-Scorpion Serum (equine source) Leiurus spp. and Androctonus scorpions Egypt

Marine animals edit

Antivenom Species Country
CSL box jellyfish antivenom Box jellyfish Australia
CSL stonefish antivenom Stonefish Australia

Snakes edit

Antivenom Species Country
PANAF PREMIUM (Sub-Sahara Africa) Purified lyophilized enzyme refined Equine Immunoglobulins [44] Echis ocellatus, Echis leucogaster, Echis carinatus, Bitis arietans, Bitis rhinoceros, Bitis nasicornis, Bitis gabonica, Dendroaspis polylepis, Dendroaspis viridis, Dendroaspis angusticeps, Dendroaspis jamesoni, Naja nigricollis, Naja melanoleuca and Naja haje India
Snake Venom Antiserum (India) Purified lyophilized enzyme refined Equine Immunoglobulins Naja naja, Vipera russelii and Echis carinatus India
INOSERP MENA (Middle East and North Africa) Bitis arietans, Cerastes cerastes, Cerastes gasperettii,Cerastes vipera, Daboia deserti, Daboia mauritanica, Daboia palaestinae, Echis carinatus sochureki, Echis coloratus, Echis khosatzkii, Echis leucogaster, Echis megalocephalus, Echis omanensis, Echis pyramidum, Macrovipera lebetina obtusa, Macrovipera lebetina transmediterranea, Macrovipera lebetina turanica, Montivipera bornmuelleri, Montivipera raddei kurdistanica, Pseuocerastes fieldi, Pseudocerastes persicus, Vipera latastei, Naja haje, Naja nubiae, Naja pallida and Walterinnesia aegyptia Spain
INOSERP PAN-AFRICA (Sub-Sahara Africa) Echis ocellatus, Bitis arietans, Dendroaspis polylepis and Naja nigricollis Spain
EchiTAbG (Sub-Sahara Africa)[45] Echis ocellatus, Echis pyramidum Wales, UK
Polyvalent snake antivenom Anavip South American rattlesnake Crotalus durissus and fer-de-lance Bothrops asper Mexico (Instituto Bioclon); South America
Polyvalent snake antivenom Saw-scaled viper Echis carinatus, Russell's viper Daboia russelli, spectacled cobra Naja naja, common krait Bungarus caeruleus India
Death adder antivenom Death adder Australia
Taipan antivenom Taipan Australia
Black snake antivenom Pseudechis spp. Australia
Tiger snake antivenom Australian copperheads, tiger snakes, Pseudechis spp., rough-scaled snake Australia
Brown snake antivenom Brown snakes Australia
Polyvalent snake antivenom Australian snakes as listed above Australia
Sea snake antivenom Sea snakes Australia
Vipera tab Vipera spp. UK
Polyvalent crotalid antivenin (CroFab—Crotalidae Polyvalent Immune Fab (Ovine)) North American pit vipers (all rattlesnakes, copperheads, and cottonmouths) North America
Soro antibotropicocrotalico Pit vipers and rattlesnakes Brazil
Antielapidico Coral snakes Brazil
SAIMR polyvalent antivenom Mambas, cobras, Rinkhalses, puff adders (Unsuitable small adders: B. worthingtoni, B. atropos, B. caudalis, B. cornuta, B. heraldica, B. inornata, B. peringueyi, B. schneideri, B. xeropaga) South Africa[46]
SAIMR echis antivenom Saw-scaled vipers South Africa
SAIMR Boomslang antivenom Boomslang South Africa
Panamerican serum Coral snakes Costa Rica
Anticoral Coral snakes Costa Rica
Anti-mipartitus antivenom Coral snakes Costa Rica
Anticoral monovalent Coral snakes Costa Rica
Antimicrurus Coral snakes Argentina
Coralmyn Coral snakes Mexico
Anti-micruricoscorales Coral snakes Colombia
crotalidae immune F(ab')2 (equine)) (Anavip) North American species of Crotalinae US

Terminology edit

The name "antivenin" comes from the French word venin, meaning venom, which in turn was derived from Latin venenum, meaning poison.[47]

Historically, the term antivenin was predominant around the world, its first published use being in 1895.[48] In 1981, the World Health Organization decided that the preferred terminology in the English language would be venom and antivenom rather than venin and antivenin or venen and antivenene.[49]

References edit

  1. ^ a b c d e f g h i World Health Organization (2009). Stuart MC, Kouimtzi M, Hill SR (eds.). WHO Model Formulary 2008. World Health Organization. pp. 396–397. hdl:10665/44053. ISBN 9789241547659.
  2. ^ a b c Dart RC (2004). Medical Toxicology. Lippincott Williams & Wilkins. pp. 250–251. ISBN 9780781728454. Archived from the original on 2017-01-09.
  3. ^ British national formulary : BNF 69 (69 ed.). British Medical Association. 2015. p. 43. ISBN 9780857111562.
  4. ^ Knudsen C, Laustsen AH (April 2018). "Recent Advances in Next Generation Snakebite Antivenoms". Tropical Medicine and Infectious Disease. 3 (2): 42. doi:10.3390/tropicalmed3020042. PMC 6073149. PMID 30274438.
  5. ^ Molteni M. "Bacteria Are Brewing Up the Next Generation of Antivenoms". Wired – via www.wired.com.
  6. ^ "How to simplify the treatment of snake bites". The Economist. 2021-01-02. ISSN 0013-0613. Retrieved 2021-01-02.
  7. ^ Gad SC (2007). Handbook of Pharmaceutical Biotechnology. John Wiley & Sons. p. 692. ISBN 9780470117101. Archived from the original on 2017-01-09.
  8. ^ World Health Organization (2019). World Health Organization model list of essential medicines: 21st list 2019. Geneva: World Health Organization. hdl:10665/325771. WHO/MVP/EMP/IAU/2019.06. License: CC BY-NC-SA 3.0 IGO.
  9. ^ "CroFab Crotalidae Polyvalent Immune Fab (Ovine)". SavageLabs.com. Archived from the original on 2016-03-03. Retrieved 2016-02-08. Link to PDF for full prescribing information, retrieved 11/11/12
  10. ^ "Coral Snake & Antivenom FAQ's". Florida Poison Information Center - Tampa. May 2017. Archived from the original on 2019-11-01. Retrieved October 31, 2019.
  11. ^ "North American Micrurus (Coral Snake Venoms)". Toxnet: Toxicology Data Network. September 15, 2015. Retrieved October 31, 2019.
  12. ^ Franklin, Deborah, "Potential Treatment For Snakebites Leads To A Paralyzing Test Archived 2014-08-09 at the Wayback Machine", NPR.org, July 31, 2013.
  13. ^ "Universal antidote for snakebite: Experimental trial represents promising step Archived 2014-07-07 at the Wayback Machine", California Academy of Sciences via Science Daily, May 28, 2014.
  14. ^ Whyte I (2012). "Antivenom update" (PDF). Australian Prescriber. 35 (5): 152–155. doi:10.18773/austprescr.2012.069.
  15. ^ Isbister GK (December 2002). "Failure of intramuscular antivenom in Red-back spider envenoming". Emergency Medicine. 14 (4): 436–439. doi:10.1046/j.1442-2026.2002.00356.x. PMID 12534488.
  16. ^ Bhoite RR, Bhoite GR, Bagdure DN, Bawaskar HS (2015). "Anaphylaxis to scorpion antivenin and its management following envenomation by Indian red scorpion, Mesobuthus tamulus". Indian Journal of Critical Care Medicine. 19 (9): 547–549. doi:10.4103/0972-5229.164807. PMC 4578200. PMID 26430342.
  17. ^ See, for example, the Antivenom Precautions paragraph of the Medication section of Forster J (2006-03-14). "Snake Envenomations, Sea". eMedicine Emergency Medicine (environmental). Archived from the original on 26 June 2006. Retrieved 2006-06-25.
  18. ^ Warrell D (2016). Guidelines for the management of snakebites (2nd ed.). New Delhi: World Health Organization. p. 111,136,192. ISBN 9788177394979.
  19. ^ Gad S. Handbook of Pharmaceutical Biotechnology. p. 692.
  20. ^ a b "Guidelines for the production, control and regulation of snake antivenom immunoglobulins" (PDF). WHO Technical Series No, 1004. WHO. 2017. Retrieved 15 January 2020.
  21. ^ "Opossum Compounds Isolated to Help Make Antivenom". Scientific American. 2015-03-30. Retrieved 2020-02-01.
  22. ^ "Ueber das Zustandekommen der Diphtherie-Immunität und der Tetanus-Immunität bei Thieren". Deutsche Medizinische Wochenschrift. 16 (49): 1113–1114. December 1890. doi:10.1055/s-0029-1207589. ISSN 0012-0472. S2CID 80469638.
  23. ^ Bochner R (8 June 2016). "Paths to the discovery of antivenom serotherapy in France". Journal of Venomous Animals and Toxins Including Tropical Diseases. 22 (20): 20. doi:10.1186/s40409-016-0074-7. PMC 4898362. PMID 27279829.
  24. ^ "Venoms, venomous animals and antivenomous serum-therapeutics / by A. Calmette ; translated by Ernest E. Austen". Wellcome Collection. Retrieved 2023-05-24.
  25. ^ "Serum Antivenimeux Desseche, 10cc - Dried Antivenin Serum for Snake Bites". Smithsonian Institution. Retrieved 2023-05-24.
  26. ^ Fontana F (1767). Ricerche fisiche sopra il veleno della vipera. Wellcome Library. In Lucca : Nella stamperia di Jacopo Giusti.
  27. ^ Bhaumik R (2018-11-01). "Colonial Encounter on Indian Snakes and their Venoms: The Transmission and Transformation of Western Ophiological Knowledge in British India, 1780s-1910s" (PDF). Indian Journal of History of Science. 53 (4). doi:10.16943/ijhs/2018/v53i4/49536. ISSN 0019-5235.
  28. ^ Bhaumik R (2018-11-01). "Colonial Encounter on Indian Snakes and their Venoms: The Transmission and Transformation of Western Ophiological Knowledge in British India, 1780s-1910s" (PDF). Indian Journal of History of Science. 53 (4). doi:10.16943/ijhs/2018/v53i4/49536. ISSN 0019-5235.
  29. ^ De Franco M, Kalil J (July 2014). "The Butantan Institute: history and future perspectives". PLOS Neglected Tropical Diseases. 8 (7): e2862. doi:10.1371/journal.pntd.0002862. PMC 4080994. PMID 24992341.
  30. ^ Jean-Philippe C, Alfredo C, Leslie B, Alejandro A (December 2020). "Factors involved in the resilience of incidence and decrease of mortality from scorpion stings in Mexico". Toxicon. 188: 65–75. doi:10.1016/j.toxicon.2020.10.011. PMID 33065199. S2CID 223558071.
  31. ^ "CSL antivenoms 1956". Power House Museum. Archived from the original on 7 August 2016. Retrieved 24 February 2017.
  32. ^ "Antivenin Nearctic Crotalidae - North American Anti-Snake-Bite Serum". Smithsonian Institution. Retrieved 2023-05-24.
  33. ^ do Amaral A (1927). Bulletin of the Antiven Institute of America. Vol. 1 (1st ed.). US: Antivenin Institute of America.
  34. ^ Rojas G, Jiménez JM, Gutiérrez JM (March 1994). "Caprylic acid fractionation of hyperimmune horse plasma: description of a simple procedure for antivenom production". Toxicon. 32 (3): 351–363. doi:10.1016/0041-0101(94)90087-6. PMID 8016856.
  35. ^ Boyer L, Degan J, Ruha AM, Mallie J, Mangin E, Alagón A (December 2013). "Safety of intravenous equine F(ab')2: insights following clinical trials involving 1534 recipients of scorpion antivenom". Toxicon. 76: 386–393. doi:10.1016/j.toxicon.2013.07.017. PMID 23916602.
  36. ^ Levine L, Broderick EJ (1970). "The plasmapheresis of hyperimmunized horses". Bulletin of the World Health Organization. 42 (6): 998–1000. hdl:10665/262354. PMC 2427561. PMID 5312259.
  37. ^ "Horses Key To Making Antivenom Up For FDA Approval". Fronteras. 2011-08-02. Retrieved 2023-05-24.
  38. ^ Agarwal R, Aggarwal AN, Gupta D, Behera D, Jindal SK (June 2005). "Low dose of snake antivenom is as effective as high dose in patients with severe neurotoxic snake envenoming". Emergency Medicine Journal. 22 (6): 397–399. doi:10.1136/emj.2004.020727. PMC 1726801. PMID 15911942.
  39. ^ Lewis D (11 September 2015). "Why a Single Vial of Antivenom Can Cost $14,000". Smithsonian. Retrieved 9 January 2017.
  40. ^ "Antivenom Supply for Snake bites". www.pharmaceutical-technology.com. 24 April 2019.
  41. ^ Theakston RD, Warrell DA, Griffiths E (April 2003). "Report of a WHO workshop on the standardization and control of antivenoms". Toxicon. 41 (5): 541–57. doi:10.1016/S0041-0101(02)00393-8. PMID 12676433.
  42. ^ Powerful new antivenom raises hopes for a universal solution to lethal snakebites (Report). 2024-02-21. doi:10.1126/science.zqvsmhr.
  43. ^ "Appendix: Antivenom Tables". Clinical Toxicology. 41 (3): 317–27. 2003. doi:10.1081/CLT-120021117. S2CID 218867125.
  44. ^ Calvete JJ, Arias AS, Rodríguez Y, Quesada-Bernat S, Sánchez LV, Chippaux JP, et al. (September 2016). "Preclinical evaluation of three polyspecific antivenoms against the venom of Echis ocellatus: Neutralization of toxic activities and antivenomics". Toxicon. Elsevier. 119: 280–288. doi:10.1016/j.toxicon.2016.06.022. PMID 27377229.
  45. ^ Snake Antivenom for Sub – Sharan Africa EchiTAbG (PDF), World Health Organization, 20 June 2019, retrieved 14 December 2019
  46. ^ Spawls S, Branch B (1995). The Dangerous Snakes of Africa. Ralph Curtis Books. Dubai: Oriental Press. p. 192. ISBN 0-88359-029-8.
  47. ^ Weinstein SA (September 2015). "Snake venoms: A brief treatise on etymology, origins of terminology, and definitions". Toxicon. Elsevier. 103: 188–195. doi:10.1016/j.toxicon.2015.07.005. PMID 26166305.
  48. ^ "Antivenin". Merriam-Webster.com Dictionary.
  49. ^ World Health Organization (1981). Progress in the characterization of venoms and standardization of antivenoms. Geneva: WHO Offset Publications. p. 5. ISBN 92-4-170058-0.

External links edit