(CNN) -- In South Korea, the abduction and rape of a 7-year-old girllast week outraged the public and prompted President Lee Myung-Bak to consider various measures including chemical castration to combat child sex crimes, according to local media.
Chemical castration involves administering medication -- via injection or tablets -- to take away sexual interest and make it impossible for a person to perform sexual acts. The effects are reversible, after the person stops taking the drug. Lee said this week that all detering measures - including chemical castration - should be considered, according to the Korea Times.
After high-profile child rape cases, politicians worldwide tend to pledge a crackdown and harsher punishments for sex offenders, involving chemical castration, said Don Grubin, professor of forensic psychiatry at Newcastle University.
"In a way, I liken it to cutting the hand off the thief," he said. "It's very symbolic."
The use of chemical castration, while effective, remains controversial. While sex offenders may not be the most sympathetic group, critics say forced chemical castration violates human rights.
The process of chemical castration has been used in various forms, either forcibly as a sentence or as a way for offenders to reduce their jail time in several countries including Argentina, Australia, Estonia, Israel, Moldova, New Zealand, Poland and Russia.
At least nine U.S. states, including California, Florida, Georgia, Iowa, Louisiana, Montana, Oregon, Texas and Wisconsin have versions of chemical castration in their laws. It's unclear how frequently chemical castration is used in the United States.
Earlier this year, Moldova legalized the practice for those convicted for child sex crimes.
The practice of forced chemical castration has been called "inhuman treatment" by Amnesty International. The group released a statement after Moldova's legalization of the practice, stating that "any crime shall be punished in a way that abides by the Universal Declaration of Human Rights. Clearly, in case of minors raped public opinion tilts towards harsher sentences.
"At first sight, forced chemical castration could be taken as a matter-of-course decision; however, it is incompatible with human rights, which are the foundation of any civilized democratic society," according to its March statement.
In May, South Korea first used chemical castration on a sex offender who had been convicted of four counts of rape or attempted rape on young girls, according to the country's Ministry of Justice. A law authorizing this treatment for sex offenders came into effect last year after a public outcry over rapists reoffending following their release.
The country could be poised to expand the use to punish those who sexually assault victims as old as 19.
"It's clear the drugs work," Grubin said. "If you look at men, they do reduce sex drive drastically. They do reduce re-offending in the men."
But they also have side effects, such as osteoporosis, changes in cardiovascular health, blood fat levels, blood pressure and symptoms that mimic women's menopause.
The use is reasonable if the offender agrees to the medication to control their sexual drive, which some do, Grubin said. And it's ideal to receive the drugs along with psychological help, he added
It becomes problematic when it is used against a person's will for non-medical reasons, Grubin said.
He wrote in a 2010 editorial in the British medical journal BMJ, "Although castration is ostensibly for public protection, it also carries with it a sense of symbolic retribution."
Physical castration has also been used for sex offenders.Physical castration removes the testicles
In 2009, the Council of Europe's Anti-Torture Committee criticized the Czech Republic for its practice of surgically castrating convicted sex offenders. The committee described the practice as "invasive, irreversible and mutilating.
This year, the same committee asked Germany to stop offering sex offenders the option of surgical castration. The procedure is not mandatory and remains very rare in Germany.
