Non-Surgical Sterilization

Non-Surgical Sterilization for Dogs

ZeuterinTM, also known as zinc neutering, can permanently sterilize male dogs with a single injection of zinc gluconate and arginine into each testicle.

  • Zeuterin is available for male dogs between three and ten months of age.
  • Size restrictions apply and are determined by clinic staff.
  • “Zeutered” dogs retain their testicles. Size and texture may change after the procedure.
    • Zeutered dogs cannot get female dogs pregnant.
    • Zeutered dogs continue to produce some testosterone.

The injections into the testicles are quick and virtually painless. All zeutered dogs have a "Z" tattoo in their groin area and are implanted with a microchip.

Zeuterin may be the preferred option for guardians that prefer to retain their dog’s testicles. Some dogs can have the Zeuterin procedure performed under light sedation, rather than general anesthesia. However, brachycephalic (flatter-faced) dogs and some others require general anesthesia for the procedure. Please see for more information. If interested, please call the San Francisco SPCA Spay-Neuter Clinic at 415.554.3030 or e-mail us at