Which of the following best describes a narcotic?

A narcotic is best described as a pain reliever usually derived from opiates. Narcotics, also known as opioids, primarily function by binding to specific receptors in the brain and spinal cord that manage pain, thereby altering the perception of pain and producing feelings of euphoria. This class of drugs includes both natural opiates derived from the opium poppy, such as morphine and codeine, and synthetic variants like oxycodone and fentanyl.

While anti-inflammatory drugs focus on reducing inflammation and are commonly used for pain relief, they do not operate via the same mechanism as narcotics. Muscle-enhancing medications, in contrast, are typically anabolic steroids and are used for performance enhancement rather than pain management. Lastly, topical treatments for muscle injuries include creams or gels that may contain analgesics or anti-inflammatories, but they do not fit the definition of a narcotic since they do not act systemically like opiates do. Thus, the characterization of narcotics as pain relievers derived from opiates encompasses their primary role in medical treatment.