Tramadol -- a prescription drug that was touted as a safe alternative to powerful opioids like oxycodone -- is of increasing concern to law and addiction experts who say children as young as 8 are experimenting with the painkiller.
This week four Utah junior high schoolers were sent to the hospital after one overdosed on what teens call "ultras" -- slang for a drug marketed under the name Ultram.
Though all the girls are fine, experts say in higher doses, the drug can stop breathing and causes seizures and death.
"While this particular drug was, a few years ago, only rarely mentioned by the teens, it does seem to have exploded in popularity over the past year," said Rick Kirkham, who chronicled his addiction to crack cocaine in the 2006 documentary "TV Junkie" and now educates students about drug use.
"Kids are now much more educated on the more 'out of the cross hairs' prescription drugs readily sitting in their family medicine cabinets," he told ABCNews.com.
Tramadol is a narcotic analgesic, or opioid, that is chemically related to codeine and is used to treat mild to moderate pain. Because of the danger of drugs like oxycodone, doctors are prescribing it more often.
Because the drug is nonscheduled, the federal Drug Enforcement Administration doesn't keep statistics on its use, but lists tramadol as a "drug of concern."
Like other prescriptions drugs, "We're seeing kids as young as 8 and 12 and they are getting it at school," DEA spokesman Garrison Courtney told ABCNews.com. "You've got to figure a lot of kids are lighter and don't have the same metabolism as adults. Adult drugs can be fatal."
"Part of the problem of pharmaceutical drug abuse is because the stigma that there is with cocaine, heroin or crack," said Courtney. "But look at Heath Ledger and Anna Nicole Smith."
More than half of people older than 12 who use pain relievers nonmedically get them free from a relative or friend, according to the National Center for Health Statistics. That troubling trend has spilled down to junior high schoolers.
The teens who were hospitalized in Utah admitted to police that one of the girls had obtained the painkillers at home and brought them to school.
A study that was released by the U.S. Department of Health and Human Services in 2007 showed Utah was No. 1 in prescription drug abuse, with about 6 percent of the population using drugs without a doctor's order.
It showed 7.88 percent of 12- to 17-year-olds and 13.49 percent of 18- to 25-year-olds used prescription painkillers for nonmedical reasons. The number was 4.32 percent for those older than 25.
"I've never seen anything like this before -- four girls at once," said Randy Ripplinger, a spokesman for the Granite School District, where the teens go to Matheson Junior High School. "One of the girls was [in] bad enough condition to be transported to the hospital. Later the principal discovered three others were in on the drug taking and transported the rest of them just so they didn't take any chances."
The girls -- all of them ninth-graders between the ages of 14 and 15 -- "didn't know what they were taking," said Marijean Woolf, principal of the 958-student school. "It surprised me."
One of the teens brought the pill to school in a small, plastic bag and offered it to two of her friends.
"The student said she had a pain in her wrist and distributed them," Woolf told ABCNews.com. "One girl ate [multiple] pills and the other girls took one."
The school counselor noticed one of the girls "not feeling well" in the hallway and intervened. Two other girls not involved in the incident reported that they had overheard conversations in the hall and worried the teens may have taken medicine.
"These young girls are not aware of how serious it could be," said Woolf, who called the paramedics.
The girls probably became nauseated after taking the painkillers, according to Dr. Lynn Willis, a pharmacologist from the Indiana University School of Medicine.
"The same thing would have happened to them if they had overdosed on Demerol, OxyContin or any other of the opioids," he told ABCNews.com.
Tramadol has been around since about 1977 but was approved as a nonscheduled painkiller -- the least-addictive type of drug, according to the U.S. government -- in 1995 and marketed by Ortho-McNeil Pharmaceutical as Ultram.
Doctors say its abuse record has been "fairly low," but that is changing.
"These girls were naive," said Dr. Andrew Kowal, director of the Pain Center at Lahey Clinic in Massachusetts. "They take one or two pills and it makes them feel dizzy, but you take too much and you can die."
The so-called "nonaddictive" nature of tramadol is precisely why it can be so dangerous, Kowal told ABCNews.com. Users don't get a euphoric "buzz," so they tend to take more of it.
But, like alcohol and heroin, tramadol is a central nervous system depressant and can cause respiratory distress in larger quantities. And because it has anti-depressant properties, it can cause seizures, even at lower doses.
Kowal has noticed an "increasing diversion" of tramadol in New England. "It's available on the street for purchase and it came from mom or dad's cabinet."
Tramadol also can be easily obtained over the Internet with a credit card and, on many sites, without a medical history or physician approval.
The National Institute on Drug Abuse offers advice on how parents can reduce the likelihood of children "pilfering" dangerous drugs from the medicine cabinet.
"If you're not taking it, dispose of it," said Dr. Wilson Compton, director of the institute's division of epidemiology services and prevention research. "If you need it on a regular basis, keep it locked up -- no matter how much you trust your own teen. There are others in the house."
Meanwhile, rather than be expelled, the four girls from Utah face the possibility of 45 days in a detention center under the school's Safe School policy. Their fate will be decided after they appear before a district committee with their parents.
Woolf went on student TV to warn of the dangers of prescription drugs and plans to speak before parents during a seminar. The school will also address the issue with counselors and in health classes.
"It was a very unusual situation, and that's why we acted so quickly and aggressively," said Woolf. "I really believe they took them with no knowledge of what it would do to them, just to have a nice time. Now we have to take care of the health of those students and educate others to those kinds of behaviors."