Delusions of pregnancy associated with increased prolactin concentrations produced by antipsychotic treatment.

Treatment of psychotic symptoms has traditionally involved conventional antipsychotics. While efficacious, their side-effects have been problematic and the approval by the Food and Drug Administration of the newer antipsychotics with improved side-effects profiles heralded important advances in treating psychoses. Prolactin elevation has been associated with all classical and some atypical antipsychotics. We present cases where elevation of prolactin concentrations secondary to antipsychotic treatment was associated with delusions of pregnancy. Risperidone was the antipsychotic employed and elevation of prolactin concentrations were noted each time. The delusions abated and prolactin concentrations decreased when the drug was discontinued. Rechallenge with risperidone resulted in re-elevation of prolactin levels along with recurrent delusions. Substituting risperidone with another antipsychotic (either olanzapine or quetiapine) also led to abatement of the delusions and lowering of prolactin. Although no direct psychotogenic effects of prolactin are known, it is contended that delusions of pregnancy reported during antipsychotic treatment might be associated with rising prolactin concentrations.