Sleeping gas

Sleeping gas is an oneirogenic general anaesthetic that is used to put subjects into a state in which they are not conscious of what is happening around them. Incapacitating agent is a related general term for "knockout gases" or "KO gas" that ideally render a person unable to harm themselves or others, regardless of consciousness. Most sleeping gases have undesirable side effects, or are effective at doses that approach toxicity.

Examples of modern volatile anaesthetics that may be considered sleeping gases are BZ,halothane vapour (Fluothane),methyl propyl ether (Neothyl), methoxyflurane (Penthrane), and the undisclosed fentanyl derivative delivery system used by the FSB in the Moscow theater hostage crisis.

Possible side effects might not prevent use of sleeping gas by criminals willing to murder, or carefully control the dose on a single already sleepy individual. There are reports of thieves spraying sleeping gases on campers, or in train compartments in some parts of Europe.Alarms are sold to detect and alert to such attacks, so some people believe sleeping gas is dangerous to health.

In a Mennonite community in Bolivia, eight men were convicted of raping 130 women in Manitoba Colony over a four-year period from 2005 to 2009, by spraying "a chemical used to anesthetize cows" through the victims' open bedroom windows. The perpetrators would then wait for the women to be incapacitated, whereupon they entered the residences to commit the crimes. Later, the women would awaken to a pounding headache, find blood, semen or dirt on their sheets, and would sometimes discover their extremities had also been bound. Most did not remember the attacks, although a few had vague, fleeting memories of men on top of them. Several men and boys were also suspected of having been raped. While additional actors were thought to have participated, they were never identified nor prosecuted; in fact, the rapes did not stop with the incarceration of the original eight men.

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