Which of the following is a characteristic of narcotics?

Narcotics, also known as opioids, are primarily recognized for their ability to manage pain and induce sleep. The characteristic that best captures their fundamental effects is the production of analgesic and hypnotic effects. Analgesic means these substances effectively reduce pain, making them crucial in various clinical and therapeutic settings where pain management is necessary. The hypnotic effect indicates their capacity to induce drowsiness or sleep, which can be beneficial for patients who need rest due to severe pain or other medical conditions.

The other options highlight aspects that do not accurately characterize the primary functions of narcotics. Some narcotics may have secondary effects that could influence anxiety or contribute to gastrointestinal issues, but these are not their defining characteristics. Instead, the core function as pain relievers and sedatives defines narcotics, making the correct option a direct reflection of their primary use and effects in medicine.