Chemical castration
Chemical castration is castration via anaphrodisiac drugs, whether to reduce libido and sexual activity, to treat cancer, or otherwise. Unlike surgical castration, where the gonads are removed through an incision in the body, chemical castration does not remove organs and is not a form of sterilization.
Chemical castration is generally reversible when treatment is discontinued, although permanent effects in body chemistry can sometimes be seen, as in the case of bone density loss increasing with length of use of depot medroxyprogesterone acetate. In men, chemical castration reduces sex drive and the capacity for sexual arousal, side effects of some drugs may include depression, suicidal ideation, hot flashes, anemia, infertility, increase in body fat and higher risks of cardiovascular diseases and osteoporosis. In women, chemical castration acts by decreasing testosterone levels in order to lower their sex drive, side effects include the deflation of breast glands, expansion of the size of the nipple and shrinking of bone mass.
In some jurisdictions, chemical castration has been used to reduce the libido of sexual offenders. The effectiveness of chemical castration in decreasing recidivism among sex offenders is controversial.
Effects
On males
When used on males, these drugs can reduce sex drive, sexual fantasies, and capacity for sexual arousal. Life-threatening side effects are rare, but some users show increases in body fat and reduced bone density, which increase long-term risk of cardiovascular disease and osteoporosis, respectively. Males may also experience gynecomastia ; full development is less common unless chemical castration is combined with feminizing oestrogen therapy.Some drugs, such as medroxyprogesterone acetate, cyproterone acetate, and LHRH agonists can decrease serum testosterone and estradiol in the body, thus impairing the metabolism of glucose and lipid. These drugs can also cause depression, hot flashes, infertility, and anemia, aside from cardiovascular diseases and osteoporosis. The risk of side effects caused by chemical castration drugs can increase depending on the length of time under which they are administered. A 2004 study in which eleven men were chemically castrated ended with one committing suicide after one year of treatment; in another 2020 study, increases in suicidal ideations was reported by 8% of its treatment group, which led to the hospitalization of two of the 25 subjects who had been administered degarelix.
On females
When used on females, the effects are similar, though there is little research about chemically lowering female's sex drive or female-specific anaphrodisiacs, since most research focuses on the opposite, but anti-androgenic hormone regimens would lower testosterone in females which can impact sex drive or sexual response. These drugs also deflate the breast glands and expand the size of the nipple. Also seen is a sudden shrinking in bone mass and discoloration of the lips, reduced body hair, and muscle mass.Treatment for sex offenders
The first use of chemical castration occurred in 1944, when diethylstilbestrol was used with the purpose of lowering men's testosterone.The antipsychotic agent benperidol was sometimes used to decrease sexual urges in people who displayed what was thought of as inappropriate sexual behavior, and as likewise given by depot injection, though benperidol does not affect testosterone and is therefore not a castration agent.
Chemical castration was often seen as an easier alternative to life imprisonment or the death penalty because it allowed the release of the convicted.
In 1981, in an experiment by Pierre Gagné, 48 males with long-standing histories of sexually deviant behaviour were given medroxyprogesterone acetate for as long as 12 months. Forty of those subjects were recorded as having diminished desires for deviant sexual behaviour, as well as less frequent sexual fantasies and greater control over sexual urges. The research recorded a continuation of this improved behaviour after the administration of the drug had ended, with no evidence of adverse side effects, and so recommended medroxyprogesterone acetate along with counselling as a successful method of treatment for serial sex offenders.
Leuprolide acetate is an LHRH agonist that is most commonly used in chemical castration today. This drug has been observed as having higher rates of success in reducing abnormal sexual urges and fantasies, but is often reserved for those offenders who are at a high risk of reoffending due to the drug's intense effects.
Psychotherapy has also recently been used in conjunction with chemical castration in order to maximize and prolong the beneficial results. Schober et al. reported in 2005 that when cognitive behavioral therapy combined with leuprolide acetetate was compared to cognitive behavioral therapy alone, the combination therapy produced a much more significant reduction of pedophilic fantasies and urges as well as masturbation. Chemical castration therapy reduces an individual's libido which then makes some offenders more responsive to the introduction of psychotherapy. This combination therapy is most often utilized in those who are at a high risk of offending.
Offering criminals the option of chemical castration for a reduction in sentence is an example of compulsory sterilization, as it can leave a subject sterile if they are required to continue treatment for more than 3 years.
In 2025, British Justice Secretary Shabana Mahmood announced that chemical castration would roll out regionally across Britain and that she would consider requiring it.
Scientific critique
Some criminologists argue that the lower recidivism rates seen in male sex offenders who undergo chemical castration might not be due to the medication's biological effects. Instead, one hypothesis is that men who agree to chemical castration — often in exchange for a shorter prison sentence — may simply be more motivated to stay out of prison than those who refuse the treatment. These men might also be more skilled at hiding any new offences, making it appear as though they reoffend less when they actually do not. Additionally, there could be investigation bias, in that police and parole officers might assume castrated men are less dangerous and therefore be less thorough when investigating them and thus causing a self-fulfilling prophecy, which could artificially lower the apparent recidivism rate. Some criminologists even suggest that offenders may sell their prescribed medications on the black market, giving them extra income to fund ways to conceal their criminal behaviour more effectively than untreated offenders.Separately, some neurologists acknowledge that testosterone plays a role in sexual arousal but argue that simply lowering sex drive may not reduce inappropriate sexual behaviour. They explain that when internal sexual arousal signals are weaker, individuals may require stronger and more specific external stimuli to achieve satisfaction. This could make it harder for former offenders to manage their remaining sex drive through ordinary masturbation without pornography or other preferred stimuli. In other words, reducing sex drive biologically might inadvertently increase the need for risky or socially unacceptable outlets rather than solving the underlying behavioural problems.
Chemical castration by country
Africa
South Africa
In July 2022, a proposed policy of chemical castration for rapists was introduced at the national policy conference of the ruling party, the African National Congress, by the party's Women's League.Americas
Argentina
In March 2010, Guillermo Fontana of CNN reported that officials in Mendoza, a province in Argentina, approved the use of voluntary chemical castration for rapists, in return for reduced sentences.United States
In 1966, John Money became the first American to employ chemical castration by prescribing medroxyprogesterone acetate as a treatment for a "Bisexual transvestite with pedophiliac homosexual incest" who was in 'treatment' after their wife informed Money about them having sexually abused their 6-year-old son. The drug has thereafter become a mainstay of chemical castration in America. Despite having been extensively used in the United States for the purpose of decreasing sexual impulses, the drug has never been approved by the FDA for use as a treatment for sexual offenders.California was the first U.S. state to specify the use of chemical castration for repeat child molesters as a condition of their parole, following the passage of a modification to Section 645 of the California penal code in 1996. This law stipulates castration for anyone convicted of child molestation with a minor under 13 years of age if they are on parole after their second offense. Offenders may not reject the intervention, although they may elect surgical castration instead of ongoing DMPA injections.
The passage of this law led to similar laws in other states such as Florida's Statute Section 794.0235 which was passed into law in 1997.
At least seven other states, including Georgia, Iowa, Louisiana, Montana, Oregon, Texas and Wisconsin, have experimented with chemical castration. In Iowa, as in California and Florida, offenders may be sentenced to chemical castration in all cases involving serious sex offenses. On June 25, 2008, following the Supreme Court ruling in Kennedy v. Louisiana that the execution of child rapists where the victim was not killed was ruled unconstitutional, Louisiana Governor Bobby Jindal signed Senate Bill 144, allowing Louisiana judges to sentence convicted rapists to chemical castration. Alabama passed such a law in 2019.
The American Civil Liberties Union of Florida opposes the administration of any drug that is dangerous or has significant irreversible effect as an alternative to incarceration; however, they do not oppose the use of antiandrogen drugs for sex offenders under carefully controlled circumstances as an alternative to incarceration. Law professor John Stinneford has argued that chemical castration is a cruel and unusual punishment because it exerts control over the mind of sex offenders to render them incapable of sexual desire and subjects them to the physical changes caused by the hormones used.
Some people have argued that, based on the 14th Amendment, the procedure fails to guarantee equal protection: although the laws mandating the treatment do so without respect to gender, the actual effect of the procedure disproportionately falls upon men. In the case of voluntary statutes, the ability to give informed consent is also an issue; in 1984, the U.S. state of Michigan's court of appeals held that mandating chemical castration as a condition of probation was unlawful on the grounds that the drug medroxyprogesterone acetate had not yet gained acceptance as being safe and reliable and also due to the difficulty of obtaining informed consent under these circumstances.