- Objective: Left prefrontal transcranial magnetic stimulation (TMS) has been reported to have ECT-like effects in depression and we therefore planned a study of TMS in mania. Sixteen patients completed trial of right versus left prefrontal TMS at 20 Hz, 2-sec duration per train, 20 trains per day for 10 treatment days. Mania was evaluated using the Mania Scale, the Brief Psychiatric Rating Scale and the Clinical Global Impression. Significantly more improvement was observed in patients treated with right prefrontal TMS than with left prefrontal. We now report a follow-up study of right active TMS versus right sham TMS with the same indications and parameters. Methods: Twenty-five patients entered and 19 completed right TMS versus sham right TMS. Results: Right TMS was no more effective than sham TMS. Conclusions: It is possible that the previous results were due to an effect of left TMS to worsen mania. Alternatively, it is noted that the present patient group had much more psychosis than the previous study of TMS in mania, and depression studies have reported that psychosis is a poor prognostic sign for TMS response.