The review currently includes nine randomised controlled trials (RCTs) with 3361 participants. The overall rate of premature study discontinuation was very high (59.1%). Data for the comparisons of ziprasidone with amisulpride, clozapine, olanzapine, quetiapine and risperidone were available. Ziprasidone was a less acceptable treatment than olanzapine (leaving the studies early for any reason: 5 RCTs, n=1937, RR 1.26 CI 1.18 to 1.35, NNH 7 CI 5 to 10) and risperidone (3 RCTs, n=1029, RR 1.11 CI 1.02 to 1.20, NNH 14 CI 8 to 50), but not than the other second generation antipsychotic drugs. Ziprasidone was less efficacious than amisulpride (leaving the study early due to inefficacy: 1 RCT, n=123, RR 4.72 CI 1.06 to 20.98, NNH 8 CI 5 to 50) olanzapine (PANSS total score: 4 RCTs, n=1291, MD 8.32 CI 5.64 to 10.99) and risperidone (PANSS total score: 3 RCTs, n=1016, MD 3.91 CI 0.27 to 7.55). Based on limited data there were no significant differences in tolerability between ziprasidone and amisulpride or clozapine. Ziprasidone produced less weight gain than olanzapine (5 RCTs, n=1659, MD -3.82 CI -4.69 to -2.96), quetiapine (2 RCTs, n=754, RR 0.45 CI 0.28 to 0.74) or risperidone (3 RCTs, n=1063, RR 0.49 CI 0.33 to 0.74). It was associated with less cholesterol increase than olanzapine, quetiapine and risperidone. Conversely ziprasidone produced slightly more extrapyramidal side-effects than olanzapine (4 RCTs, n=1732, RR 1.43 CI 1.03 to 1.99, NNH not estimable) and more prolactin increase than quetiapine (2 RCTs, n=754, MD 4.77 CI 1.37 to 8.16), but less movement disorders (2 RCTs, n=822, RR 0.70 CI 0.51 to 0.97, NNT not estimable) and less prolactin increase (2 RCTs, n=767, MD -21.97 CI -27.34 to -16.60) than risperidone.