What term is used to describe illegal drugs or controlled substances?

The term that is commonly used to describe illegal drugs or controlled substances is "narcotics." This term encompasses a broad range of drugs that can induce sedation and pain relief, but it is also often associated with substances that are illegal or heavily regulated due to their potential for abuse and addiction. Narcotics generally refer to opioids, which include both naturally derived substances, like morphine, and synthetic ones, like fentanyl.

While stimulants, barbiturates, and hallucinogens are all categories of drugs, they do not collectively cover the wide spectrum of illegal substances in the same way that narcotics do. Stimulants primarily increase alertness and energy, barbiturates are a class of depressants used primarily for anxiety and insomnia, and hallucinogens alter perception and cognition. Therefore, the identification of narcotics as a term for illegal drugs reflects the legal and medical frameworks in which these substances are categorized, focusing on their potential for harm and how they are regulated by law.