Although it is still cited in diagnostic manuals of psychiatry, such as DSM-IV and in the International Statistical Classification of Diseases and Related Health Problems (ICD), oneirophrenia as a separate entity is out of fashion nowadays.
[citation needed] Oneirophrenia was studied in the 1950s by the neurologist and psychiatrist Ladislas J. Meduna (1896–1964), also known as the discoverer of one of the forms of shock therapy, using the drug metrazol.
Psychoanalysts, such as Claudio Naranjo, in the sixties have described the value of ibogaine-induced oneirophrenia for inducing and manipulating free fantasy and dream-like associations in patients under treatment.
Oneirophrenia has some of the characteristics of schizophrenia, such as a confusional state and clouding of consciousness, but without presenting the dissociative symptoms which are typical of that disorder.
Persons affected by oneirophrenia have a feeling of dream-like derealization which, in its extreme form, may progress to delusions and hallucinations.