(CNN) - News of students at the University of Tennessee using "alcohol enemas" to get drunk prompted a slew of comments from CNN readers in disbelief.
"When I was in college we just did funnels and kegstands," said commenter LogicBomb101.
"Is there a 12-step program for that?" FootnoteFad asked.
But alcohol enemas are no laughing matter, experts say. One of the Tennessee students was taken to the hospital with a blood alcohol level of 0.40, officials said. That's five times the legal limit and in what doctors call the "death zone" for alcohol poisoning.
Using an alcohol enema involves placing a small tube into someone's rectum and pouring alcohol directly into the colon. Because the alcohol is absorbed directly into the bloodstream, the recipient gets drunk faster.
Our stomachs and livers have an enzyme known as alcohol dehydrogenase that breaks down ethanol to make it less toxic for our bodies, said Atlanta gastroenterologist Dr. Preston Stewart. The lower gastrointestinal tract doesn't have that enzyme, so alcohol molecules are absorbed into the bloodstream through the lining of the colon.
Eventually the alcohol would still make its way to the liver, Stewart said, but the high alcohol content would overwhelm the organ. "It's extremely dangerous."
No one is sure when alcohol enemas first appeared on the social scene or how frequently they're being used.
In 2004, a Texas man died after his wife gave him a sherry enema, causing his blood alcohol level to soar to 0.47.
"In the past year or so there have been several stories about young people finding unique ways to get alcohol in their bodies," said Dr. Aaron White, with the National Institute on Alcohol Abuse and Alcoholism.
Fortunately, he said, they seem to be isolated incidents.
While it's not known what motivated the young men in Tennessee to participate in this risky behavior, White said several factors could have been at play. One is the sense of competition among college drinkers who always want to "win" at games like beer pong and flip cup. It could also have been simple boredom, or curiosity.
Many young adults believe inserting alcohol into another orifice will reduce the chance that they'll spend the night hung over a toilet vomiting. That makes it all the more dangerous, because your body can't reject the toxin, White said.
"When you do it rectally you may still throw up, but there's nothing to throw up here. It's kind of like a point of no return once you put it in there that way."
Robert Pfeifer, founder of the rehab center Sober College, said he's seen an increase in risky behavior in young adults over the last year, from "bath salts" drugs to synthetic marijuana to vodka tampons. As their bodies develop a tolerance for toxic substances, abusers seek out stronger and faster highs.
"There certainly are signs that are out there that people have gone over the edge and need to get some help," Pfeifer said. "Behaviors like this -- that's definitely a sign."
If you or someone you know has an alcohol abuse problem, please visit the Substance Abuse and Mental Health Services Administration at http://www.samhsa.gov/ or call 1-800-662-HELP.