Inhaled nitrous oxide, a party drug more commonly known as laughing gas, whip-its and "hippie crack," provides relatively intense, brief highs, although few people realize it also can harm, or even kill.
Despite a benign reputation for reducing users to peals of laughter, the colorless, sweet-smelling gas deprives the heart and brain of oxygen and can cause damage. Nitrous oxide use is what reportedly landed actress Demi Moore in the hospital this week, according to the website TMZ.com, which posted statements from a friend who was at the 49-year-old actress's home when she lapsed into semi-consciousness.
Moore's publicist on Thursday declined to comment beyond the statement issued earlier in the week that the actress was receiving medical treatment.
"Because of the stresses in her life right now, Demi has chosen to seek professional assistance to treat her exhaustion and improve her overall health. She looks forward to getting well and is grateful for the support of her family and friends," her rep said in an email to ABCNews.com.
Nitrous oxide interacts with the brain's reward system to cause "out-of-body, mild, hallucinatory, euphoric-type stuff," said Dr. Terry Horton, chief of addiction medicine at Christiana Care Health System in Wilmington, Del. "To some folks, that's appealing."
The buzz is fleeting, lasting just a minute or two, while "the potential dangers are many," Horton told ABCNews.com. Although Horton wasn't involved in Moore's treatment and wasn't familiar with the specifics of her case, he said coverage of nitrous oxide's effects on Moore could underscore its dangers, or backfire "if there's a sense out there that whip-its are not going to cause problems, and this PR perpetuates that."
Nitrous oxide use can be particularly dangerous for someone who has a history of abusing drugs or alcohol, according to Denise Carise, chief clinical officer at the Phoenix House Foundation in New York. "Often, the use of one drug can lead to the use of the person's drug of choice and new problems," she said. "We don't often see fatalities or brain damage from the abuse of nitrous oxide in isolation, but it's use is often associated with drinking and other risky behavior that can cause serious problems."
Nitrous oxide has legitimate uses as a mild anesthetic and pain-reliever, an engine booster in auto racing and rocketry, and to dispense whipped cream from pressurized spray cans (which is the source of its nickname -- written whip-its, whippits or whippets). Easily accessible, relatively inexpensive and generally legal -- although many states restrict sales to minors -- nitrous oxide has escaped the bad rap of other mood-altering drugs. Sir Humphry Davy, the British chemist who discovered its anesthetic properties in 1799, reported becoming intoxicated after breathing 16 quarts of the gas for almost seven minutes. Through much of the 1800s, it remained a largely recreational drug among poets and aristocrats, and had another surge of popularity among beat generation writers and artists of the 1950s.