Risperidone versus haloperidol in the treatment of schizophrenia: a meta-analysis comparing their efficacy and safety

The aim of this study was to compare the short-term clinical efficacy and safety of risperidone with haloperidol and placebo. A meta-analysis of seven published randomized double-blind controlled trials was carried out. Study quality was assessed. The proportion of patients failing to reach at least 20% improvement on the positive and negative syndrome scale (PANSS) or brief psychiatric rating scale (BPRS), the proportion of patients discontinuing treatment because of adverse effects and the number of patients who needed antiparkinsonian medication were abstracted for use as outcome measures. Treatment failure was present in 50% of risperidone-treated patients compared to 66% in those treated with haloperidol and 83% in those treated with placebo. It would be necessary to treat 11 patients with risperidone to prevent one treatment failure in those patients treated with haloperidol (Odds ratio (OR) = 0.74, 95% CI of 0.58-0.94, P = 0.02). Pooling of the three multicentre trials which included placebo as a treatment arm, showed that one in three patients treated with risperidone 4-16 mg/day (OR = 0.22, 95% CI of 0.13-0.39, P < 0.00001) and one in six treated with haloperidol 10-20 mg/day. (OR = 0.44, 95% CI of 0.22-0.84, P = 0.02) would derive significant benefit. Moreover, there was a highly significant greater need for anticholinergic medication due to extrapyramidal symptoms (EPS) in the haloperidol-treated patients compared to risperidone (OR = 0.54, 95% CI of 0.42-0.70, P < 0.00001). In conclusion, risperidone seems to be more effective and causes less EPS than haloperidol, as suggested by the significantly lower requirement for antiparkinsonian medication.