Zeuterin (''zū-tur-in'') is the trade name of an injectable product containing

zinc gluconate 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% eleme ...

and the amino acid arginine, which is used for sterilizing young male dogs without the removal of the testicles. The product is injected directly into the testicle, where the zinc gluconate destroys the sperm and causes

inflammation Inflammation (from la, inflammatio) is part of the complex biological response of body tissues to harmful stimuli, such as pathogens, damaged cells, or irritants, and is a protective response involving immune cells, blood vessels, and molec ...

, which leads to

fibrosis Fibrosis, also known as fibrotic scarring, is a pathological wound healing in which connective tissue replaces normal parenchymal tissue to the extent that it goes unchecked, leading to considerable tissue remodelling and the formation of perma ...

and causes sterility. 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. Following administration, the testicles atrophy; the degree of atrophy may vary noticeably between testicles. The male hormone,

testosterone Testosterone is the primary sex hormone and anabolic steroid in males. In humans, testosterone plays a key role in the development of male reproductive tissues such as testes and prostate, as well as promoting secondary sexual characteristi ...

, is produced in limited quantities following treatment with Zeuterin, but after two years, testosterone production is similar to that in untreated dogs. 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 medicine, a contraindication is a condition that serves as a reason not to take a certain medical treatment due to the harm that it would cause the patient. Contraindication is the opposite of indication, which is a reason to use a certain tre ...

in cases of undescended testicles (

cryptorchidism Cryptorchidism, also known as undescended testis, is the failure of one or both testes to descend into the scrotum. The word is from Greek () 'hidden' and () 'testicle'. It is the most common birth defect of the male genital tract. About 3% of ...

), or if

scrotal The scrotum or scrotal sac is an anatomical male reproductive structure located at the base of the penis that consists of a suspended dual-chambered sac of skin and smooth muscle. It is present in most terrestrial male mammals. The scrotum co ...

dermatitis Dermatitis is inflammation of the skin, typically characterized by itchiness, redness and a rash. In cases of short duration, there may be small blisters, while in long-term cases the skin may become thickened. The area of skin involved can ...

or testicular disease is present. If the product is not injected correctly, scrotal ulceration and swelling may occur. 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. In the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territori ...

, this product was approved by the

Food and Drug Administration The United States Food and Drug Administration (FDA or US FDA) is a List of United States federal agencies, federal agency of the United States Department of Health and Human Services, Department of Health and Human Services. The FDA is respon ...

in 2003, under the trade name Neutersol, and was marketed from 2003 to 2005 by Pet Healthcare International. 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. Outside of the United States, Zeuterin is known by the trade name Esterilsol.

References

{{Reflist Dog medications