Investigated the efficacy and safety of risperidone in the long-term treatment of schizophreniThe authors present the results of the Jordan part of an international, multicenter, open label study. 58 15-60 yr old patients with acute exacerbation of chronic schizophrenia were included in the study and treated for 7 mo. Results show that there was statistically significant improvement in psychopathology in all patients who completed the study (15 patients dropped out). The mean Positive and Negative Symptom Scale score at selection was 104.2 and was reduced to 49.2 at the end. The mean percentage of improvement after 7 mo. was 52.4%. Changes in Clinical Global Impression scores were consistent with these improvements, confirming that the changes were clinically meaningful. Extrapyramidal side effects reached 6.8%, but other adverse effects were minimal. It is concluded that risperidone affects positive and negative symptoms as well as anxiety, depression and hostility associated with chronic schizophrenia, and with a substantially favorable safety and tolerability profile in long-term use.