There are millions of unwanted dogs for whom surgical sterilization is not an option due to a lack of funding, clinics, and human resources (veterinarians). A possible solution is non-surgical sterilization of male dogs. Two non-surgical options are Zeuterin and the use of compounded calcium chloride dihydrate (CaClCa). Current studies and usage experiments are ongoing and more research is needed. 

An important part of any sterilization program is marking or tattooing all dogs to prevent re-capture.


The Wall Street Journal

CaClCa was featured in the Wall Street Journal as "A cheap, quick, relatively painless procedure could make a big dent in canine overpopulation." They also call out why the pharmaceutical industry has nothing to gain in its funding and efficacy tests.


Featured in the Wall Street Journal, SpayFirst in Oklahoma is leading the charge in CaClCa research. The treatment uses a common chemical salt, averaging to about $1 per dog! They are convinced of the safety and efficacy of the drug.


Purchase Calcium Chloride

CaClCa is not patented – and is available in the U.S. and every country with access to the two ingredients (calcium chloride dihydrate, and pharmaceutical-grade or food-grade pure ethyl alcohol). It can be ordered by veterinarians from a reputable compounding pharmacy (20% (w/v) Calcium Chloride Dihydrate, USP in Ethyl Alcohol 190 proof, USP) or it can be prepared under sterile conditions.

Another option is to purchase it directly (as we have) from Calcium Chloride Castration, a Canadian company led by Peter Denooij, DVM.

Other Resources

Parsemus Foundation – Helping spread the word, lists SpayFirst
ACC&D – Lists international presentations on CaClCa
2014 Acta Veterinaria Scandinavica Study; Leoci, Aiudi, Silvestre, Lissner, Lacalandra
2011 Chilean Study (Spanish): Morales, Contardo, Cifuentes, Rojas