What distinguishes controlled substances from non-controlled substances?

Controlled substances are specifically distinguished from non-controlled substances primarily by their potential for abuse and dependency. The classification of a substance as controlled is largely based on its likelihood to be misused, which often leads to physical or psychological dependence. Regulatory authorities, such as the Drug Enforcement Administration (DEA), assess these substances according to criteria that consider abuse potential, medical use, and safety.

Many controlled substances are associated with a higher risk for addiction and have more stringent regulations governing their prescription, distribution, and use. This categorization is reflected in the scheduling system, where drugs are classified into schedules ranging from I to V based on their potential for abuse and accepted medical use. For instance, Schedule I substances are deemed to have no accepted medical use and a high potential for abuse, while Schedule V substances have lower risk and more accepted medical uses.

Other options do not play a central role in differentiating controlled from non-controlled substances. While effectiveness or labeling requirements might vary between categories of drugs, they do not directly impact the classification based on the risk of abuse and dependency. Similarly, the availability over-the-counter does not inherently define a substance as controlled or non-controlled, since many non-controlled substances can also have varying availability forms.