Zeuterin (zū-tur-in) is the trade name of an injectable product containing zinc gluconate and the amino acid arginine, which is used for sterilizing young male dogs without the removal of the testicles.

• Macpherson, CNL; Meslin, F-X; Wandeler, AI, eds. (2012). “Chemosterilants”. Dogs, zoonoses and public health (2nd ed.). Wallingford, Oxfordshire: CABI. p. 265. ISBN 9781845938352.

The product is injected directly into the testicle, where the zinc gluconate destroys the sperm and causes inflammation, which leads to fibrosis and causes sterility.

•  Romich, Janet Amundson (2005). “Male hormone-like drugs”. Fundamentals of pharmacology for veterinary technicians. Clifton Park, NY: Thomson Delmar Learning. pp. 162–4. ISBN 9781401842932.
• “Zeuterin/Esterilsol: Product profile and position paper” (PDF). Alliance for Contraception in Cats & Dogs. June 2015. Retrieved 2017-05-20.

Sperm production continues for up to 60 days after product administration, and in some dogs does not stop completely, although the product is 99.6% effective when given to dogs aged 3-10 months of age. 

• Tobias, KM; Johnston, Spencer A. (2011). “Nonsurgical sterilization techniques”. Veterinary Surgery. London: Elsevier Health Sciences. p. 1910. ISBN 9780323263375.
• Tobias, KM (2011). “Chapter 29: Canine Castration – Chemical castration”. Manual of Small Animal Soft Tissue Surgery. John Wiley & Sons. ISBN 9781119949541.

Following administration, the testicles atrophy; the degree of atrophy may vary noticeably between testicles. 

• Romich, Janet Amundson (2005). “Male hormone-like drugs”. Fundamentals of pharmacology for veterinary technicians. Clifton Park, NY: Thomson Delmar Learning. pp. 162–4. ISBN 9781401842932.

The male hormone, testosterone, is produced in limited quantities following treatment with Zeuterin, but after two years, testosterone production is similar to that in untreated dogs. 

• Macpherson, CNL; Meslin, F-X; Wandeler, AI, eds. (2012). “Chemosterilants”. Dogs, zoonoses and public health (2nd ed.). Wallingford, Oxfordshire: CABI. p. 265. ISBN 9781845938352.

The continuing presence of testosterone means that, unlike surgical castration, chemical castration does not remove the risk of testosterone-associated disease, such as prostatic disease. This method of chemical castration is contraindicated in cases of undescended testicles (cryptorchidism), or if scrotal dermatitis or testicular disease is present. 

• Romich, Janet Amundson (2005). “Male hormone-like drugs”. Fundamentals of pharmacology for veterinary technicians. Clifton Park, NY: Thomson Delmar Learning. pp. 162–4. ISBN 9781401842932.

If the product is not injected correctly, scrotal ulceration and swelling may occur.

•  Macpherson, CNL; Meslin, F-X; Wandeler, AI, eds. (2012). “Chemosterilants”. Dogs, zoonoses and public health (2nd ed.). Wallingford, Oxfordshire: CABI. p. 265. ISBN 9781845938352.

The manufacturer, Ark Sciences, certifies veterinarians to use Zeuterin after they have completed a 5-hour course regarding the correct location and manner to inject the drug.

• Quenqua, Douglas (2 December 2013). “New Strides in Spaying and Neutering”. The New York Times Company. Retrieved 2017-05-20.

In the United States, this product was approved by the Food and Drug Administration in 2003, under the trade name Neutersol, and was marketed from 2003 to 2005 by Pet Healthcare International.

• “Zeuterin/Esterilsol: Product profile and position paper” (PDF). Alliance for Contraception in Cats & Dogs. June 2015. Retrieved 2017-05-20.

In 2005, Pet Healthcare International severed ties with its manufacturing partner Addison Biologicals, and production of the drug stopped. Ark Sciences acquired the intellectual property to Neutersol, rebranded it as Zeuterin, and relaunched it in 2014. In 2016, Ark Sciences suspended distribution of Zeuterin.

• “Zeuterin/Esterilsol: Product profile and position paper” (PDF). Alliance for Contraception in Cats & Dogs. June 2015. Retrieved 2017-05-20.
• Neutersol and Esterilsol: Injectable Sterilization for Male Dogs”. Retrieved 3 January 2010.
•  “Ark Sciences Releases Canine Sterilization Drug”. Veterinary Practice News. 18 February 2014. Retrieved 2017-05-20.
• Lau, Edie (22 April 2016). “Zeuterin marketer falters two years after U.S. debut – VIN”. The VIN News Service. Retrieved 2017-05-20.

Outside of the United States, Zeuterin is known by the trade name Esterilsol.

•  Macpherson, CNL; Meslin, F-X; Wandeler, AI, eds. (2012). “Chemosterilants”. Dogs, zoonoses and public health (2nd ed.). Wallingford, Oxfordshire: CABI. p. 265. ISBN 9781845938352.

Zinc gluconate is the zinc salt of gluconic acid. It is an ionic compound consisting of two anions of gluconate for each zinc(II) cation. Zinc gluconate is a popular form for the delivery of zinc as a dietary supplement providing 14.35% elemental zinc by weight.

Gluconic acid is found naturally, and is industrially made by the fermentation of glucose, typically by Aspergillus niger, but also by other fungi, e.g. Penicillium, or by bacteria, e.g. Acetobacter, Pseudomonas and Gluconobacter. In its pure form, it is a white to off-white powder. It can also be made by electrolytic oxidation, although this is a more expensive process. The advantages are a lower microbiological profile, and a more complete reaction, yielding a product with a longer shelf life.

• Sumitra Ramachandran, Pierre Fontanille, Ashok Pandey and Christian Larroche (2006). “Gluconic Acid: A Review” (PDF). Food Technology and Biotechnology. 44 (2): 185–195. Retrieved 2006-12-06.
• Henk G.J. de Wilt (1972). “Part I: The oxidation of Glucose to Gluconic Acid”. Ind. Eng. Chem. Prod. Res. Develop. 11 (4): 370. doi:10.1021/i360044a002.

zinc gluconate Safety concerns

Instances of anosmia (loss of smell) have been reported with intranasal use of some products containing zinc gluconate. In September 2003, Zicam faced lawsuits from users who claimed that the product, a nasal gel containing zinc gluconate and several inactive ingredients, negatively affected their sense of smell and sometimes taste. Some plaintiffs alleged experiencing a strong and very painful burning sensation when they used the product. Matrixx Initiatives, Inc., the maker of Zicam, responded that only a small number of people had experienced problems and that anosmia can be caused by the common cold itself. In January 2006, 340 lawsuits were settled for $12 million.

• Jafek, Bruce W.; Linschoten, Miriam R.; Murrow, Bruce W. (2004). “Anosmia after intranasal zinc gluconate use” (PDF). Am. J. Rhinol. 18 (3): 137–141. doi:10.1177/194589240401800302. PMID 15283486. S2CID 12554540.
• Alexander, Thomas H.; Davidson, Terence M. (2006). “Intranasal zinc and anosmia: The zinc-induced anosmia syndrome”. The Laryngoscope. 116 (2): 217–220. doi:10.1097/01.mlg.0000191549.17796.13. PMID 16467707. S2CID 39830031.
• D’Cruze, Hubert; Arroll, Bruce; Kenealy, Tim (2009). “Is intranasal zinc effective and safe for the common cold? A systematic review and meta-analysis”. J. Prim. Health Care. 1 (2): 134–139. doi:10.1071/HC09134. PMID 20690364.
• Davidson, Terence M.; Smith, W. M. (2010). “The Bradford Hill criteria and zinc-induced anosmia: A causality analysis”. Arch. Otolaryngol. Head Neck Surg. 136 (7): 673–676. doi:10.1001/archoto.2010.111. PMID 20644061.
• zicam.vanosteen.com Archived June 22, 2007, at the Wayback Machine

The U.S. Food and Drug Administration (FDA) considers zinc gluconate to be generally recognized as safe (GRAS) when used in accordance with good manufacturing practice, although this does not constitute a finding by the FDA that the substance is a useful dietary supplement. On 16 June 2009 the FDA “warned consumers to stop using and discard three zinc-containing Zicam intranasal products. The products may cause a loss of sense of smell. … FDA is concerned that the loss of sense of smell may be permanent.” Matrixx responded that the FDA’s allegations were “unfounded and misleading”, citing a lack of evidence from controlled tests that Zicam causes anosmia. In its warning, the FDA stated, “This warning does not involve oral zinc tablets and lozenges taken by mouth. Dietary zinc is also not subject to this warning.”

•  “Title 21, Part 182 Substances Generally Recognized as Safe (21CFR182)”. United States Code of Federal Regulations. Food and Drug Administration, Department of Health and Human Services. Retrieved 2007-07-09.
• “Warnings on Three Zicam Intranasal Zinc Products”. www.fda.gov. Archived from the original on 17 June 2009. Retrieved 13 January 2022.
• “FDA Advises Consumers Not to Use Certain Zicam Cold Remedies”. www.fda.gov. Archived from the original on 17 June 2009. Retrieved 13 January 2022.
• “FDA warns against using 3 popular Zicam cold meds”. CNN. 2009-06-16. Retrieved 2010-04-29.

Categories: 

• Dog medications
• Chemosterilants
• Dietary supplements
• Gluconates
• Zinc compounds

Other Notes

Despite the low cost and other purported benefits, high volume castrators were not at all interested in this thing. What, if anything, does that have to do with the collection of reproductive body parts and/or obfuscation of widespread (reproductive?) poisoning of man and beast? and what, if anything, does this have to do with zinc becoming a thing in the 1930s? or being found in ancient discoveries (roman ships?) and called the oldest pills? (for sore eyes? the same romans whose entire way of life depended upon castrated slaves? were they reading too much? you know that’s not right). and what about modern day sunscreen that they were and probably still are slopping all over kids, with or without parental permission at the suggestion of “healthcare” which, once again, has eradicated nothing but life itself for all of recorded history? I’m sure there are other products and history to look at. questions for another day…