Which opioid is schedule III and used for nonproductive cough?

• A. Diphenoxylate
• B. Hydrocodone
• C. Morphine
• D. Codeine

Answer: (B)

Opioids can suppress coughing by acting on the medullary cough center in the brain, providing relief from a nonproductive cough. Hydrocodone, when used in combination products (for example with acetaminophen), is classified as Schedule III because these formulations have a lower potential for abuse relative to the most tightly controlled opioids, while still serving an approved medical use. This makes hydrocodone a practical antitussive in nonproductive coughs in many clinical contexts.

Diphenoxylate is geared toward treating diarrhea, not cough, so it isn’t used for this purpose. Morphine is a potent opioid with a higher risk profile and is placed in a stricter schedule. Codeine is an opioid antitussive as well, but its scheduling varies by formulation and regulatory authority, whereas the question’s described category points to the hydrocodone combination products.