WAUKESHA COUNTY - It's used to treat heroin addicts; a prescription drug that saves lives. But it can also take them.

Now police are working to get the prescription drug off the street.

We rode along with undercover officers as they took down a drug dealer in a shopping center parking lot in Waukesha County. It was a marijuana bust, but the Waukesha County Metro Drug Unit also targets dealers selling prescription meds.

Investigators will tell you the drug world is trendy, and these days Suboxone is an emerging threat in southeast Wisconsin.

"I think Suboxone's tied in with the rise in heroin. If they can't find heroin and don't want to go through the withdrawals they'll get the Suboxone," an undercover officer told us.

The drug is used to wean addicts.

Taken the wrong way, it's deadly. Three teenagers died after using Suboxone illegally this year. Two UWM freshmen and Whitefish Bay teen Maddie Kiefer. In all three cases the teenagers mixed Suboxone with other drugs or alcohol.

"If you get enough, you stop breathing, and that's how people die," Dr. Basil Jackson commented. The Menomonee Falls psychiatrist says Suboxone works, every time. It weans people off their addiction without creating a new one. "The beauty about the drug is even if they have to remain on it for a long time it's still effective and it's still safe."

Mary Portis calls it "a miracle pill." She credits Suboxone for doing what she couldn't. "Your body aches, constantly throwing up. You're hot and cold you can't eat," she said. The prescription drug turned Portis into a recovering heroin addict.

Portis, a mother and grandmother, tried to go clean a number of times but always relapsed. Now that she's sober, Portis is also changing her lifestyle. "I spend more time with my grand kids now that I'm clean, whereas before I was always in the streets."

And on the streets Suboxone's in demand. During our ride along, the drug unit tries to make a buy. It never happened. The dealer was all out of Suboxone.

In 2008, there were not any busts for Suboxone in Waukesha County. This year the drug unit has already made several arrests.

The drug is popular among young people because it's cheap. Suboxone is sold by the pill, which can cost as little as three bucks on the street.

Some states are having problems with doctors who sell Suboxone prescriptions for money. There has been no evidence of that happening in Wisconsin.