What is the primary characteristic of a Schedule I drug?

The primary characteristic of a Schedule I drug is its high abuse potential and lack of accepted medicinal value. This classification, as outlined in the Controlled Substances Act, is reserved for substances that are considered to have a high potential for abuse and do not have an accepted medical use in treatment in the United States. Examples of Schedule I drugs include substances like heroin and LSD, which have been determined to pose significant risks of dependency and misuse without providing any legitimate medicinal benefit.

In contrast, drugs in other categories, such as those with low abuse potential and high medicinal value, are classified as Schedule IV or V, indicating their safer profile and medicinal applications. The lack of recognition for medicinal use is a defining factor for Schedule I substances, setting them apart from those that can be prescribed or utilized in clinical settings.