Sildenafil adjunctive therapy to risperidone in the treatment of the negative symptoms of schizophrenia: a double-blind randomized placebo-controlled trial.

RATIONAL: It has been suggested that phosphodiesterase 5 inhibitors such as sildenafil may be effective in the treatment of negative symptoms of schizophrenia. OBJECTIVE: This study was designed to investigate the effect of sildenafil added to risperidone as augmentation therapy in patients with chronic schizophrenia and prominent negative symptoms in a double-blind and randomized clinical trial. METHODS: Eligible participants in the study were 40 patients with chronic schizophrenia with ages ranging from 18 to 45 years. All patients were inpatients and were in the active phase of the illness and met DSM-IV-TR criteria for schizophrenia. Patients were allocated in a random fashion: 20 to risperidone (6 mg/day) plus sildenafil (75 mg/day) and 20 to risperidone (6 mg/day) plus placebo. The principal measure of outcome was Positive and Negative Syndrome Scale (PANSS). RESULTS: Although both protocols significantly decreased the score of the positive, negative, and general psychopathological symptoms over the trial period, the combination of risperidone and sildenafil showed a significant superiority over risperidone alone in decreasing negative symptoms and PANSS total scores over the 8-week trial (between-subjects factor; F = 4.77, df = 1; P = 0.03; F = 5.91, df = 1, P = 0.02 respectively). CONCLUSION: Therapy with 75 mg/day of sildenafil was well tolerated, and no clinically important side effects were observed. The present study indicates sildenafil as a potential adjunctive treatment strategy for treatment of negative symptoms of schizophrenia. This trial is registered with the Iranian Clinical Trials Registry (IRCT1138901151556N11).

Double-blind, randomized, placebo-controlled 6-week study on the efficacy and safety of the tamoxifen adjunctive to lithium in acute bipolar mania.

BACKGROUND: Considerable amount of biochemical data supports the potential involvement of protein kinase C in the pathophysiology and treatment of bipolar disorder. The aim of this double-blind, placebo-controlled study was to investigate the efficacy and tolerability of tamoxifen as an adjunct to lithium for the treatment of acute mania in hospitalized bipolar patients. METHODS: Eligible participants were 40 inpatients, between the ages of 19 and 49 years with current manic episode. Patients were randomly allocated to lithium (1-1.2 mEq/L) + tamoxifen 80 mg/day (group A) or lithium (1-1.2 mEq/L) + placebo (group B) for a 6-week, double-blind, placebo-controlled study. The principal measure of outcome was the Young Mania Rating Scale. The raters used standardized instructions for Young Mania Rating Scale. RESULTS: Young Mania Rating Scale scores improved with tamoxifen. The difference between the two protocols was significant as indicated by the effect of the group, the between-subjects factor (F=5.41, df=1, p=0.02). A significant difference was observed on the Positive and Negative Syndrome Scale total score at week 6 in the two groups. The difference between the two groups in the frequency of side effects was not significant except for fatigue that occurred more often in the tamoxifen group. LIMITATIONS: Tamoxifen is an antagonist of estrogen receptor as well. CONCLUSION: The results demonstrate that the combination of tamoxifen with lithium was superior to lithium alone for the rapid reduction of manic symptoms. The combined use of tamoxifen with lithium was well tolerated in these acutely manic patients.