The intravenous route is not FDA approved and is generally not recommended except when no other alternatives are available. Intravenous administration appears to be associated with a higher risk of QT prolongation and torsade de pointes (TdP) than other forms of administration. The manufacturer recommends ECG monitoring for QT prolongation and arrhythmias if IV administration is required. A dose in the range of 1 to 5 mg IV has been suggested, with the dose being repeated at 30 to 60 minute intervals, if needed. A maximum IV dose has not been established. The lowest effective dose should be used in conjunction with conversion to oral therapy as soon as possible.
Acute psychosis, although not recognized as a diagnostic term in DSM-5 is commonly used to describe a rapid deterioration of behavior associated with hallucinations and delusions. Schizophreniform disorder, brief psychotic disorder, and organic psychoses fall under this rubric. The DSM-5 diagnosis of schizophreniform disorder depends on the persistence of schizophrenia-like symptoms for at least 1 month and exclusion of other causes of acute psychosis. Brief psychotic disorder (often referred to as brief reactive psychosis) lasts less than 1 month, but more than 1 day. It is typically regarded as a reaction to marked stress in persons with borderline or antisocial personality disorders.