An East Bridgewater mother is asking state lawmakers to criminalize a drug she says killed her 15-year-old daughter after she used it just once.

The drug is a synthetic hallucinogen known as "25I," "N-Bomb," or sometimes "Smiles."

Erin Valentine has made it her mission to warn other parents about the drug. She and the doctors who tried to save her daughter Emily had never heard of the substance until June. That's when she learned Emily and a friend who was sleeping over had slipped out of the house in the middle of the night, and she brought them home from some nearby baseball fields.

Erin Valentine, right, with her daughter Emily. Emily was 15 when she died in June from septic shock and organ failure after taking the drug 25I. (Courtesy Erin Valentine)

"I started to hear Emily in a moaning, weird voice, in long, stretched out, saying, 'Oh my God,' really loud. 'This is crazy. I can't believe we did this,' " Valentine recalled.

Emily had never snuck out before and was a good student, her mother said. But she had been suffering some psychiatric issues including depression and had recently started hanging around with a new crowd.

When she heard Emily moaning that night she ran into her room and asked the girls what they had done. They told her they had ingested something yellow and black or blue. Within minutes things took a turn for the worse for Emily.

"She was violently thrashing her arms and her head back and forth, hitting the wall with her arms," Valentine said. "I straddled her and held her arms and I was trying to look into her eyes, and I said, 'Emily, you're going to hurt your arm, honey. What's happening?' And she's going, 'Help me, help me, help me!' And her eyes are rolling back in her head and I'm holding her."

Valentine said Emily was sweating profusely, and then her jaw and hands started stiffening.

An ambulance rushed her to Brockton Hospital, where her heart stopped three times. She was then med-flighted to Mass General Hospital. While she was in a medically induced coma, Emily's friends contacted her mother saying Emily had talked about possibly trying the drug 25I-NBOMe, a LSD-like substance. They showed Valentine a social media post in which Emily said someone had offered her the drug, and she was worried about how she might react to it.

"And she wrote that 'the worst thing that could happen to me will be that I'll get a serotonin headache.' So she clearly thought it through — obviously not accurately," Valentine said.

The drug 25I activates receptors in the body for the neurotransmitter serotonin. It's said to make some users feel euphoric and mentally stimulated. But for Emily, the drug damaged her liver. Then she got an infection that brought about septic shock and liver failure. She died three weeks after entering the hospital.

Valentine said because the doctors hadn't heard of the drug, by the time they located a toxicology test for it, it was too late to detect it. But Valentine has no doubt 25I is to blame for Emily's death, and not because it interacted with the prescribed psychiatric medication Emily was also taking.

"The doctors were quite confident that it was not drug-drug interaction, because it was such a violent, massively destructive, quick response," she explained.

Law enforcement is trying to quickly learn about 25I, but right now police can't charge people for having it.

"It's not a controlled substance in Massachusetts because it doesn't fall under any of our categories," said Middlesex County District Attorney Marian Ryan. "So police can't take it. They can't stop people. Even if they saw them using it, they can't stop them."

Ryan heard about 25I from several police departments, and she asked state Rep. Cory Atkins to file legislation criminalizing it.

Right now, police can only charge adults with things like reckless endangerment for supplying minors with the drug.

"It's very dangerous, even in tiny doses," Ryan said. "One of the forms it takes is drops — eye drop kind of things. And even one drop can be very damaging."

The drug also comes in blotter paper tabs, which Ryan points out are openly sold on the Internet as cheap as $5 each.

"They come in a sheet, almost like stamps. And you rip off, the way that LSD was sold for a long time," Ryan explained. "It's got a substance on the top. And they're not plain. The ones that we're seeing are marketed with little characters. You know, Pokemon, little monkey, animal-type characters — the sort of things that would be appealing to kids."

Reports indicate kids as young as middle school age are being sickened by 25I, and at least 19 people in the U.S. — including Emily Valentine — have died from it. Some have died from injuries sustained in violent reactions like Emily had — thrashing around and throwing their bodies into walls, poles and other objects.

Erin Valentine says Emily bought the 25I from a boy she knew. Valentine works as a chemist at a pharmaceutical company and hopes schools will talk with kids about 25I and other synthetic drugs. She now tells any parent she meets about the dangers of just one use of a seemingly harmless drug-dusted tab of paper.

"This is crazy. I have to do something. It's my responsibility as a parent and as a human being," Valentine said. "We have more and more people going the 'Breaking Bad' way and making their own drugs. They're drug dealers. And they're killing people, for $5."

The bill to criminalize 25I never made it to the full House for a vote in the last legislative session. But Rep. Atkins re-filed it this week.