What is a common characteristic of both opiates and opioids?

The primary characteristic that defines both opiates and opioids is their potential to cause addiction. Opiates, which are derived directly from the opium poppy (such as morphine and codeine), and opioids, which include synthetic or semi-synthetic drugs that mimic opiate effects, both activate the brain's reward system. This activation can lead to physical dependence and addiction, where an individual may develop cravings and seek out these substances compulsively, often despite negative consequences.

In the context of medical use, both opiates and opioids are prescribed for pain relief, so the idea that both have no medical use is incorrect. Furthermore, while they may alleviate some symptoms of anxiety or discomfort, they are not primarily used for anxiety treatment, and their classification and effects differ markedly from stimulants. Thus, the characteristic of addiction serves as a crucial warning regarding the use and management of these substances.