Why are some drugs described as psychotomimetic?

Some drugs are described as psychotomimetic because they induce alterations in behavior and personality that mimic the symptoms of spontaneously occurring psychosis.21

The term is derived from the words psychotic and mimetic (meaning "to mimic"). These substances, which are often classified as hallucinogens, produce profound distortions in perception, thought, and observable behavior without causing a loss of consciousness.21

Researchers and clinicians have historically studied these compounds to create "model psychoses" in an effort to better understand the underlying mechanisms of severe psychiatric conditions and to develop more effective treatments. While some individuals may use these substances in search of expanded perceptual horizons, it is important to recognize that they can produce dangerous psychological changes, including the disruption of ego defenses and the induction of emotional instability.1