Recent developments in the management of delusional disorders

Delusional phenomena, so clearly described in psychiatric textbooks, are rarely unambiguous in practice. The textbook characteristics of incorrigibility, demonstrable falseness and cultural incongruity are rarely clear-cut in real life, and normal beliefs pass into a continuum of delusionlike experiences, overvalued ideas, preoccupations, obsessions, partial delusions and delusions proper, which can exist at varying levels of conviction and bizarreness. Nowhere is this complexity more apparent than in the diagnostic category of delusional disorders, resurrected from Kraepelin’s ‘paranoia’ in DSM-III-R and continuing largely unchanged into DSM-IV (American Psychiatric Association 1987, 1994) and, reportedly, DSM-5 (www.dsm5.org).