What are "designer drugs" commonly defined as?

Designer drugs are defined as synthetic substances that are engineered to replicate the effects of existing illicit drugs. This is done by modifying the chemical structure of a known substance to create a new compound. These alterations often aim to produce similar psychoactive effects while evading legal restrictions.

Many designer drugs are created in clandestine laboratories, and their composition can vary significantly from batch to batch, increasing the potential for unpredictable and dangerous effects. The focus on mimicking the effects of well-known drugs contributes to their popularity among users seeking similar experiences without the legal complications associated with the original substances.

The other options address substances that do not align with the specific definition of designer drugs. Stimulants derived from natural herbs do not fall under the category as they are not synthetically created. Over-the-counter medications, while sometimes misused recreationally, are not designed specifically to mimic illicit drug effects. Prescription drugs used for non-medical purposes also differ, as they are legitimate medications that do not seek to replicate the effects of illegal substances in the same manner as designer drugs.