Castration includes surgical or chemical castration in which an individual loses use of the testicles. Surgical castration includes removal of both the testis, whereas chemical castration means use of medicinal drugs to render the testis nonfunctional.

In surgical castration, removal of both the testis is done (bilateral orchidectomy). Chemical castration is done by use of medicinal drugs to make the testis non functional. This reduces the libido and sexual activity too.

Castration is done for the following reasons
- to treat testicular torsion
- for gangrene of testis
- to remove dead tissue when there is trauma to testis due to sports, radiation, cancer chemotherapy, force
- to treat breast cancer or prostate cancer for reduction of testosterone levels in blood
- to treat testicular cancer

The long term effects of castration in men include
- suppression of bone growth
- low sexual drive, infertility
- mood changes, depression
- reduction in bone strength and muscle mass

Castration is done by surgical or chemical methods. In surgical castration, both the testis are surgically excised which is also known as bilateral orchidectomy.