How can drugs be diverted into the black market?

In the context of drug use, the term "diversion" refers to the illegal redirection of prescription drugs from legitimate channels—such as manufacturing, distribution, and medical practice—into the illicit or black market.1

This process occurs when controlled substances, which are regulated by agencies like the Drug Enforcement Administration (DEA) due to their potential for abuse and dependence, are obtained through unauthorized means. Common methods of diversion include:1

• Illegal Prescribing and Dispensing: Physicians or pharmacists may intentionally prescribe or provide controlled substances outside of legitimate medical necessity.1
• Theft and Fraud: Drugs may be stolen from pharmacies, warehouses, or medical facilities. Additionally, individuals may use fraudulent prescriptions or "doctor shopping"—visiting multiple physicians to obtain multiple prescriptions for the same controlled substances—to acquire drugs for non-medical use.1
• Unauthorized Redistribution: Patients or other individuals who legally obtain prescription medications may sell or trade them to others, moving them from the legal supply chain into the black market.1

It is important to distinguish this from "diversion programs" in the criminal justice system, which are strategies designed to steer nonviolent offenders toward treatment rather than incarceration.2