Psychotic symptoms frequently occur in bipolar disorder, especially in younger patients. However, whether the association with younger age also extends to psychotic symptoms that have traditionally been associated with schizophrenia, such as Schneiderian first-rank symptoms (FRSs), is unclear. This study examined FRSs in bipolar I patients and their relationship to age and gender. The sample comprised 103 consecutive inpatients who met DSM IV criteria for bipolar disorder, manic or mixed. FRSs were rated with the Scale for the Assessment of Positive Symptoms (SAPS). Interaction between FRSs and gender and FRSs and age was assessed using logistic regression. A high rate of FRSs in manic and mixed patients was found with a higher frequency in men (31%) than in women (14%; P=0.038). A monotonic increase in the association between FRSs and younger age was apparent (odds ratios (OR) over five levels: 1.42; 1.00-2.01). These results confirm previous findings that FRSs are not specific to schizophrenia and suggest in addition that a dimension of nuclear psychotic experiences of developmental origin extends across categorically defined psychotic disorders.