Which of the following is a key characteristic of a 'Controlled Substance Analogue'?

A Controlled Substance Analogue is defined as a substance that is chemically similar to a controlled substance listed in Schedule I or II of the Controlled Substances Act. This similarity means that the analogue can evoke effects similar to those of the controlled substance, which is why it is often of concern in the context of drug enforcement and regulation.

This characteristic is essential because it establishes the legal framework under which analogues may be treated similarly to their controlled counterparts, thus subjecting them to similar legal restrictions and scrutiny. The chemical similarity is a primary factor in determining the potential for abuse and the physiological effects that such substances may have.

The other choices highlight factors that do not accurately describe the nature of a Controlled Substance Analogue. For instance, while some analogues may be studied for research purposes, they are not always restricted to such use. Furthermore, many analogues may indeed have some medicinal properties, contradicting the assertion that they lack medicinal use. Lastly, stating that an analogue is recognized as safe for consumption is misleading, as many analogues pose significant health risks similar to those of the substances they mimic.