Which schedule of controlled substances is recognized for having the highest potential for abuse?

Schedule I substances are classified as having a high potential for abuse and are considered to have no accepted medical use in the United States. This category includes drugs such as heroin, LSD, and cannabis, which are strictly regulated due to their severe psychological and physical dependency risks. The absence of accepted medical use signifies that these substances are viewed as dangerous, contributing to their designation as having the highest potential for abuse among all schedules.

In contrast, Schedule II substances are recognized as having a high potential for abuse as well, but they do have accepted medical uses, albeit with severe restrictions. This difference in accepted medical use sets Schedule I apart with the highest level of concern regarding abuse potential.