What are hallucinogens known for?

Hallucinogens are primarily known for their ability to cause hallucinations, which are perceptual experiences that can occur in the absence of an external stimulus. These substances can alter a person's perception of reality, leading to vivid imagery, altered sounds, and unusual sensations. This characteristic sets hallucinogens apart from other types of drugs that might induce different effects such as sedation, pain relief, or mood changes. The ability to provoke such profound changes in perception is central to the definition and study of hallucinogenic substances in the field of health and communication. Understanding this mechanism can help in discussions around drug effects, therapeutic uses, and potential risks associated with these substances.