An open, randomized, comparative study of efficacy and safety of risperidone and haloperidol in schizophrenia

In the last decade there have been numerous randomized controlled trials comparing the efficacy and safety of second generation antipsychotics and conventional antipsychotics in the treatment of schizophrenia, but most of them have been conducted in the western population. This study compared the efficacy and safety of risperidone versus haloperidol in the Nepalese context, in order to add on to the very few literatures available on this topic in the South East Asia region and compare them.

Patients with the diagnosis of schizophrenia were randomly assigned to receive risperidone 4-6 milligrams (mg) per day and haloperidol 10-20 mg per day, and were followed up for 6 weeks. Assessment were done on the day of the diagnostic interview and days 7, 14, 28 and 42 (end point). During the assessment periods Positive and Negative Syndrome Scale (PANSS) was administered to monitor the progress in psychopathology and Udvalg for Kliniske Undersogelser (UKU) side effects rating scale was applied to rate the treatment emergent adverse effects.

Both risperidone and haloperidol were associated with substantial baseline- to- endpoint reduction in symptom severity. After one week of treatment, the improvement in schizophrenia with risperidone was significantly better than haloperidol in terms of PANSS- total Score (-45.4 versus -29.5), negative subscale score (-14.3 versus -6.68) and general psychopathology subscale score (-20.9 versus -13.7). At the end point of the study, the benefit was maintained in total score (-52.1 versus -43.1), though the negative subscale score still showed tendency for greater improvement in psychopathology with risperidone. The side effects profile did not show significant differences except in extrapyramidal symptoms. Thirty-eight percent of risperidone treated patients had to resort to anti-parkinsonian treatment compared to 78% in haloperidol treatment group.

Similar to the studies in the western countries, Asia and Indian subcontinent, both risperidone and haloperidol were effective in the reduction of psychopathological symptoms in this group of Nepalese population with the diagnosis of schizophrenia. However, risperidone was quicker and better then haloperidol and risperidone had a better safety profile. This is important, because extrapyramidal side effects of neuroleptics are responsible for non-compliance and increased cost in terms of us of anti-parkinsonian medication.