Benefits of trazodone and mianserin for patients with late-life chronic schizophrenia and tardive dyskinesia: an add-on, double-blind, placebo-controlled study

The objective of the present study was to evaluate the efficacy of mianserin and trazodone as antidepressants with serotonin 2 antagonist properties on negative symptoms and tardive dyskinesia in elderly patients with chronic schizophrenia. In this double-blind, placebo-controlled study the dose of each drug was increased gradually, from 20 mg/day mianserin to 60 mg/day, and from 50 mg/day trazodone to 200 mg/day. Symptoms were assessed using the Brief Psychiatric Rating Scale, the Scale for Assessment of Negative Symptoms and the Abnormal Involuntary Movement Scale every week for 5 weeks. A total of 38 patients (23 men and 15 women) completed the trial. Mianserin (n = 13) and trazodone (n = 12) did not alter the Brief Psychiatric Rating Scale positive symptom factor over the 5 weeks. In the mianserin group, the Scale for Assessment of Negative Symptoms total score decreased significantly after 5 weeks. Scores of 'affective flattening and blunting' and 'alogia' scores on the Scale for Assessment of Negative Symptoms decreased significantly in both treatment groups. In the trazodone group, the decrease in the Abnormal Involuntary Movement Scale total score was statistically significant at weeks 2 and 3. Results indicate that serotonergic antidepressants, when used in conjunction with neuroleptics, are safe and effective for treating negative symptoms in elderly patients with chronic schizophrenia. Results also indicated a possible beneficial effect of trazodone in treating tardive dyskinesia.