Which of the following best describes a "controlled substance"?

A controlled substance is defined as a drug that poses a risk of addiction or abuse and is regulated by law. This classification is crucial in the field of pharmacy and public health, as it helps to manage and monitor drugs that have the potential for misuse, dependence, or harmful effects. Controlled substances are categorized into schedules (I to V) based on their potential for abuse and accepted medical use, which facilitates regulatory control and informs health care providers and patients about their appropriate prescribing and dispensing.

The regulation of controlled substances is important to maintain public safety, ensuring that these drugs are prescribed and used correctly to minimize risks of addiction and abuse. Various laws, including both federal and state regulations, govern their distribution and usage, making it clear that these substances require careful oversight.

The other options do not accurately capture the nature of controlled substances. Over-the-counter medications, while they can be regulated, do not fall under the controlled substance category as they typically do not pose the same level of risk for abuse. A prescription medication used according to the label is safe and legal, but this definition does not encompass all controlled substances, as some may be misused even when prescribed properly. Lastly, stating that a medication is only available in hospitals is too restrictive and does not reflect the