Which of the following medications is classified as a Schedule IV substance due to its potential for abuse?

Zolpidem, commonly known by its brand name Ambien, is classified as a Schedule IV controlled substance due to its potential for abuse and dependence. Schedule IV substances are recognized as having a lower potential for abuse compared to those in higher schedules but still have the potential to lead to limited physical or psychological dependence. Zolpidem is primarily prescribed for the short-term treatment of insomnia, and while effective for this purpose, it can lead to misuse, particularly when taken inappropriately or in higher doses than prescribed. Patients may experience euphoria or a sedative effect, which contributes to its potential for abuse.

In contrast, Buspirone (Buspar), Hydroxyzine (Visteril), and Ramelteon (Rozerem) are not classified as Schedule IV substances. Buspirone is primarily used for anxiety and does not have a significant potential for abuse. Hydroxyzine is an antihistamine also used for anxiety and as a sedative but is not considered to have abuse potential. Ramelteon, a melatonin receptor agonist, is used to treat insomnia and has no abuse potential, making it non-controlled. Thus, Zolpidem's classification reflects the need to regulate its prescription to mitigate the risks of dependency