A study of 182 people in Spain compared the effectiveness and side effects of three anti-psychotic drugs : haloperidol, risperidone and olanzapine. The researchers concluded that all three drugs were equally effective. Haloperidol increased tremors and restlessness while olanzapine lead to weight gain. Both olanzapine and haloperidol caused increased sleepiness.
Crespo-Facorro, B. ... [et al] - A practical clinical trial comparing haloperidol, risperidone, and olanzapine for the acute treatment of first-episode nonaffective psychosis Journal of Clinical Psychiatry 2006, 67: 1511-1521