Final answer:
A combination drug containing acetaminophen and codeine is classified as a Schedule III (C-III) controlled substance, indicating a moderate to low potential for abuse and dependence.
Step-by-step explanation:
A combination drug containing acetaminophen and codeine is classified as a Schedule III (C-III) substance under the Controlled Substances Act in the United States. Codeine is an opioid with relatively low potency, often prescribed for mild to moderate pain, and when combined with acetaminophen, it is used to increase the efficacy of the pain relief process. This classification reflects a moderate to low potential for physical and psychological dependence.
Medications containing hydrocodone, which is also an opioid but is considered more potent than codeine, are classified differently. Hydrocodone combination products are often used to treat moderate-to-severe pain or as a cough suppressant. Each drug schedule reflects the substance's accepted medical use and its potential for abuse and dependency, with Schedule II (C-II) substances having a higher potential for abuse compared to Schedule III (C-III).