Final answer:
PCP was developed as a general anesthetic in the 1950s but was discontinued due to severe side effects, including confusion and delirium. The drug's history highlights the complexities of drug effects on the human brain and has shifted from medical use to being recognized for its potential for abuse.
Step-by-step explanation:
PCP, or Phencyclidine, was originally developed in the 1950s as a general anesthetic for surgery. This dissociative drug was intended to be used during medical procedures to induce a state of unconsciousness and provide pain relief. However, the use of PCP was discontinued in medical settings due to significant side effects, including confusion and delirium, which outweighed the benefits as an anesthetic. While PCP did have initial applications in the medical field, it was found to have neuroleptic properties, similar to the effects of chlorpromazine, which did not cause a loss of consciousness but produced a tendency to sleep and disinterest in surroundings.
The potential for abuse and the development of severe psychological reactions ultimately led to its discontinuation for human medical use. Presently, it is recognized as a drug of abuse, known for its capacity to induce schizophrenic-like episodes, hallucinations, and disconnection from reality, among other effects. Despite the development of other medications like mefloquine with a longer half-life, PCP's history as a medical agent serves as a cautionary tale about the complexities of drug effects on the human brain.