Recent pop-culture references to "Molly," or powdered ecstasy, has a U.S. addictions expert concerned that a longtime club drug is gaining mainstream popularity.

Popular artists like Trinidad James, Kanye West and Nicki Minaj have made references in their songs to Molly, which is a slang term for methylenedioxymethamphetamine (MDMA) in powder form.

Originally synonymous with ecstasy, MDMA has long been a popular drug in the club scene, but its latest popularization as Molly worries Dr. Joseph Lee, medical director with Hazelden Youth Continuum, a substance abuse rehabilitation program based in Minnesota.

"It's pretty much the same compound, but now it's gained popularity for a number of reasons, one of which is that people believe that it is now more pure and that it comes in a powder form as opposed to the cutesy pill form that it came in before," Lee told CBC News.

Winnipeg police say there has not been an escalation of MDMA in the city, but the drug is still commonly available in bars and on the streets.

Patrick Scribner, a recovering drug and alcohol addict in Winnipeg, said he hasn't heard of the new name, but he said MDMA continues to have wide appeal.

"It's a cheap drug … it's a very euphoric high, and it lasts quite a few hours," he said.

Mix of drugs

Lee said Molly is being promoted as the purest and safest form of MDMA, but he warned that it's usually a mix of other drugs.

"This year alone, I've seen a number of cases of kids who have used Molly and found out they were actually using methamphetamine or other derivatives that are close to MDMA but are not, and they've paid the price for it," he said.

MDMA generally creates feelings of euphoria, but Lee said some young people who have used Molly experienced very different reactions.

"Some kids who use contaminants or just have a bad reaction to MDMA itself, they can become incredibly anxious," he said.

"Some kids have seizures, some kids become depressed and suicidal the morning after, and I've seen some kids become psychotic — that is, they lose kind of a sense of what's real or not."