The benefits of surgical castration... without surgery or anaesthetic

What is the medical or non-surgical castration option?

It is a resorbable contraceptive implant administered by your veterinarian. It is inserted under the skin between your dog’s shoulders; there is no need for an anaesthetic or surgery. It is suited to dog owners who want the benefits of castration without the need for surgery, anaesthetic, or testes removal.

How does it work?

It is implanted in a simple process similar to microchipping. After implant placement, an active ingredient is released steadily, preventing the production of the sex hormones and testosterone.


Testosterone is generally reduced 2–3 weeks following implantation. It takes around 6 weeks for the dog to become infertile due to sperm stored in the reproductive tract. Depending on the implant used, sperm production is prevented for at least 6 months or at least 12 months. Once the implant wears off the dog’s fertility will gradually return.*  To maintain infertility, an implant can simply be administered either every 6 months or every 12 months depending on the implant used.


The implant is safe and not associated with significant side effects.

Benefits of medical castration
  • Helps to address behavioural problems which may be testosterone-related#

  • May alleviate diseases that are dependent on testosterone (e.g. prostatic enlargement)

  • Reversible reproductive control*

  • Provides the benefits of low testosterone now and the flexibility to allow testosterone to return*

*Discuss the expected length of time of return to fertility with your veterinarian.
#Behaviour problems are not always due to testosterone. Please talk to your vet who will be able to advise what is best for your dog.


Want to trial the effects of castration prior to permanent surgery
Would like to road test the behavioural response to lowered testosterone
Have a geriatric dog with benign prostatic hyperplasia
Want the benefits of low testosterone but may want to breed in the future*
Want the benefits of castration without surgery, general anaesthesia or testes removal
Allows you to reverse castration and for testosterone levels to return

Want to know more?

Talk to your vet to find out if medical castration may be suitable for your dog.


Download medical castration information