While studying pharmacology, the nursing student learns that a naturally occurring narcotic drug with analgesic and antitussive effects is:

Codeine

Explanation:

Codeine is an opiate and is used to treat mild and moderate pain. It is also the main ingredient in prescription based cough suppressant. It belongs to a class of drugs known as opioid analgesics.

Codeine is a naturally occurring phenanthrene alkaloid with opioid agonist and can be extracted directly from the plant although most codeine is synthesized from the opium poppy.