Define "counterfeit drug."

A counterfeit drug is defined as a medication that is falsely labeled and may contain incorrect ingredients or none at all. This definition is crucial in the context of pharmaceutical safety and regulation, as counterfeit drugs pose significant risks to patients. These medications might mimic legitimate drugs in appearance but can be substandard in quality or entirely fraudulent, potentially leading to ineffective treatment or harmful reactions.

In contrast, other definitions provided highlight different aspects of drug quality or labeling. A medication that is labeled correctly but lacks potency refers to quality issues rather than falsification. A medication that is no longer marketed by its original manufacturer does not imply any deceit in labeling or composition. Similarly, a medication that is packaged improperly may not necessarily be counterfeit; it could simply result from manufacturing or storage errors rather than intentional misrepresentation. The essence of counterfeit drugs lies in the deliberate act of deception regarding their identity and composition, which is encapsulated in the correct definition provided.