Grandiose delusions (GD) or delusions of grandeur is principally a subtype of delusional disorder that occurs in patients suffering from a wide range of mental illnesses, including two-thirds of patients in manic state of bipolar disorder, half of those with schizophrenia and a substantial portion of those with substance abuse disorders.Diagnostic and Statistical Manual of Mental Disorders Fourth edition Text Revision (DSM-IV-TR) American Psychiatric Association (2000) GDs are characterized by fantastical beliefs that one is famous, omnipotent, wealthy, or otherwise very powerful.