Chemical castration is something of a misnomer. The injection of certain drugs into a man's body does not result in castration. Rather, these drugs significantly lower a man's testosterone level and reduce his sexual desire or libido. There are three common chemical castration methods.
The most common type chemical castration is the drug Depo Provera. In women, it is used as a birth control drug. In men, Depo Provera causes a reduction in testosterone level, which usually decreases sex drive. Male sex offenders are injected on a weekly or monthly basis.
This form of chemical castration is said to be effective in a single type of sex offender known as a paraphiliac. This type of sex offender commits sex offences because they are sexually aroused by the act.
Other types of sex offenders that are motivated by violence or other non-sexual factors that are not likely to respond to this type of treatment.
Injecting Depo-Lupron into a male's body is another means of chemical castration. Depo-Lupron is a synthetic form of the hormone leuprolide. It causes overproduction of certain hormones causing production of testosterone to stop.
The elimination of testosterone production in a man's body drastically reduces or eliminates his sex drive. The goal of treatment is to eliminate the desire of a sex offender who is motivated by sexual arousal to reoffend.
Antiandrogens are another method of chemical castration. Antiandrogens work by blocking certain receptors in the body to which testosterone attaches.
The goal is to block the effects of testosterone on the male body and return levels to that of a prepubescent boy. The sex offender experiences reduced libido, theoretically eliminating the desire of a sex offender to reoffend.