Calcium chloride could be a boon to animal shelters in other impoverished areas, many of which lack the funds and the facilities to sterilize dogs surgically. More than 3 million dogs and cats are euthanized in US shelters every year. But few veterinarians and shelter operators even know about calcium chloride. Its been stalled in a regulatory Catch-22 that illustrates how products that dont have much profit potential can languish unused.
Cheap, nonsurgical sterilization would also be a godsend to countries like India, where packs of dogs run wild. World-wide, an estimated 375 million stray dogs are terrorizing neighborhoods, fighting over food and reproducing exponentially.
Research on calcium chloride goes back to the 1970s, when it was tested as a sterilizing agent in calves, colts and other animals. In the past decade, researchers in India published a dozen studies using it in dogs, cats and goats.
In three studies researchers in Bari, Italy, tested a variety of doses and solutions in 80 dogs over one year and concluded that a 20% solution of calcium chloride in ethyl alcohol was optimal, rendering dogs azoospermic (without sperm) and reducing testosterone levels by 70%, with no adverse effects. Calcium chloride isnt approved by the Food and Drug Administration and probably will never be. Its such a common chemical that it cant be patented. As a result, drug companies arent interested in investing the $10 million or more needed to run the required clinical trials. Without FDA approval, most veterinary and animal-welfare groups are leery of endorsing it.
Finding safe, nonsurgical ways to control animal reproduction has been a goal of animal researchers for decades, but progress has been slow. Some stakeholders want contraceptive approaches that will drive business to veterinarians offices; some want methods that can be provided for pennies in the field. Some animal-rights activists insist that street dogs and strays shouldnt have a lower standard of care than house pets. Some oppose doing research of any kind on animalseven to advance animal medicine. The politics are more complicated than the chemistry, says Elaine Lissner, director of the Parsemus Foundation, a nonprofit that works to advance neglected medical research.
Ms. Lissner tried to start the FDA approval process for the use of calcium chloride in male cats last year, but her bid for a barrier to innovation waiver of the $87,000 application fee was denied on the grounds that the research wasnt innovative enough. The nonprofit Alliance for Contraception in Cats and Dogs considers calcium chloride experimental and calls for more research. Some vets are horrified at the idea, says the groups president, Joyce Briggs. Because the ingredients are readily available, she says, theres concern that crazy cat ladies will be mixing this up on their kitchen table and saying, Here, kitty, kitty, kitty. Instead, the alliance is supporting a rival, FDA-approved sterilant called Zeuterin, which works much the same way. Its available for about $20 a dose to nonprofits, but it doesnt cut testosterone as significantly, which some shelters see as important to reduce aggression.
A few US vets and shelters are quietly starting to use calcium chloride. Rose Wilson, who supervises an animal shelter in Lawton, OK, has been using the drug since last spring, with the blessing of city officials. She says that she wouldnt go back to surgeries. We havent seen any problems with it, she says. Its simple, its inexpensive, and its painless. This is the best thing thats happened in the spay/neuter world in a long, long time.