What is the characteristic of Schedule I controlled substances?

Schedule I controlled substances are defined by their particularly stringent classification due to their highest potential for abuse and the fact that they lack accepted medical use in the United States. This classification indicates that these substances pose significant risks of addiction and misuse, thus they are strictly regulated and legally prohibited outside of specific research settings.

The absence of any accepted medical use distinguishes Schedule I substances from those in other schedules, which may have therapeutic applications alongside varying levels of abuse potential. For example, substances in Schedule II may have high abuse potential but are still recognized for their medical utility. Thus, Schedule I substances represent a unique category that encompasses both high abuse potential and the absence of legitimate medical use. This distinction is critical in understanding the legal and medical landscape surrounding controlled substances.