Which schedule consists of drugs that have a high potential for abuse and no accepted medical use, such as heroin?

The classification of drugs into schedules is based on their potential for abuse, medical use, and safety or dependence liability. Schedule I drugs are defined as having a high potential for abuse, and they do not have any accepted medical use in treatment in the United States. This schedule includes substances such as heroin, which are considered extremely addictive and pose significant risks to public health.

In contrast, substances classified in the other schedules (like Schedule II, III, and IV) have accepted medical uses but also carry a risk of abuse and dependence to varying degrees. Schedule II drugs have a high potential for abuse but are recognized for their medical applications, while Schedule III and IV drugs have progressively lower potentials for abuse and milder restrictions compared to Schedule I. Therefore, substances like heroin fit solely within Schedule I due to their lack of accepted medical use and high abuse potential.