Which of the following medications is NOT a Schedule II controlled substance?

The identification of controlled substances is crucial for understanding pharmacy law and regulations. In this case, Estratest is the medication that is not classified as a Schedule II controlled substance.

Schedule II controlled substances are substances recognized as having a high potential for abuse, which may lead to severe psychological or physical dependence. Cocaine, oxymorphone, and pentobarbital all fall within this category due to their potential for abuse and addiction. Cocaine, for instance, is a powerful stimulant with a high potential for misuse, while oxymorphone is a potent opioid analgesic often used for severe pain management. Pentobarbital, a barbiturate, is also recognized for its potential for abuse and is tightly controlled.

In contrast, Estratest is a combination product used for hormone replacement therapy, containing esterified estrogens and methyltestosterone. It does not have the same level of abuse potential that characterizes Schedule II substances and is classified differently under the controlled substances schedules. This classification typically places Estratest into a lower schedule or potentially not at all, which makes it distinct from the other options listed in the question. Thus, recognizing the classifications of these substances helps in identifying their legal status and the regulations surrounding their prescription and use.