Arizona MPJE (Pharmacy Jurisprudence) Practice Exam

The combination of Difenoxin 0.5mg and Atropine 25mcg is classified under which controlled substance schedule?

1. CI

2. CII

3. CV

4. CIV

The correct answer is: CI

The combination of Difenoxin 0.5 mg and Atropine 25 mcg is classified as a Schedule CV controlled substance. In the United States, medications that contain low concentrations of certain narcotics, paired with non-narcotic ingredients, may be classified under Schedule V if they meet specific criteria. Difenoxin is a derivative of diphenoxylate and is sometimes used as an antidiarrheal, while Atropine is included to discourage misuse due to the potential for abuse when used alone. The classification as a Schedule V substance comes from regulations that consider both the potential for abuse and the accepted medical use of the drug. Difenoxin, in this combination, has a lower potential for abuse and a recognized medicinal purpose, which aligns with the criteria for this less restrictive schedule. Understanding the scheduling system is crucial for pharmacists, as it helps ensure compliance with federal and state regulations regarding the dispensing of controlled substances. The other schedules, CI through CIII, have medications that are either considered to have high potential for abuse or have a higher potential for physical or psychological dependence, which does not apply in this case with Difenoxin and Atropine.