What is a Trap House? - Trap houses are dangerous places for people to get their hands on drugs, especially heroin. They are often filled with drugs that addicts can't get off of without medical attention. Several deaths have been reported in trap houses in recent years, and they often play an important role in the spread of these dangerous drugs. In a recent story on U.S. News, an Iraq veteran described how he used heroin that was laced with fentanyl, and how the withdrawal was excruciating. The drug is also addictive.