Droperidol for psychosis-induced aggression or agitation

People experiencing acute psychotic illnesses, especially those associated with agitated or violent behaviour, may require urgent pharmacological tranquillisation or sedation. Droperidol, a butyrophenone antipsychotic, has been used for this purpose in several countries.

To estimate the effects of droperidol, including its cost-effectiveness, when compared to placebo, other 'standard' or 'non-standard' treatments, or other forms of management of psychotic illness, in controlling acutely disturbed behaviour and reducing psychotic symptoms in people with schizophrenia-like illnesses.

We updated previous searches by searching the Cochrane Schizophrenia Group Register (18 December 2015). We searched references of all identified studies for further trial citations and contacted authors of trials. We supplemented these electronic searches by handsearching reference lists and contacting both the pharmaceutical industry and relevant authors.

We included all randomised controlled trials (RCTs) with useable data that compared droperidol to any other treatment for people acutely ill with suspected acute psychotic illnesses, including schizophrenia, schizoaffective disorder, mixed affective disorders, the manic phase of bipolar disorder or a brief psychotic episode.

For included studies, we assessed quality, risk of bias and extracted data. We excluded data when more than 50% of participants were lost to follow-up. For binary outcomes, we calculated standard estimates of risk ratio (RR) and the corresponding 95% confidence intervals (CI). We created a 'Summary of findings' table using GRADE.

We identified four relevant trials from the update search (previous version of this review included only two trials). When droperidol was compared with placebo, for the outcome of tranquillisation or asleep by 30 minutes we found evidence of a clear difference (1 RCT, N = 227, RR 1.18, 95% CI 1.05 to 1.31, high-quality evidence). There was a clear demonstration of reduced risk of needing additional medication after 60 minutes for the droperidol group (1 RCT, N = 227, RR 0.55, 95% CI 0.36 to 0.85, high-quality evidence). There was no evidence that droperidol caused more cardiovascular arrhythmia (1 RCT, N = 227, RR 0.34, 95% CI 0.01 to 8.31, moderate-quality evidence) and respiratory airway obstruction (1 RCT, N = 227, RR 0.62, 95% CI 0.15 to 2.52, low-quality evidence) than placebo. For 'being ready for discharge', there was no clear difference between groups (1 RCT, N = 227, RR 1.16, 95% CI 0.90 to 1.48, high-quality evidence). There were no data for mental state and costs.Similarly, when droperidol was compared to haloperidol, for the outcome of tranquillisation or asleep by 30 minutes we found evidence of a clear difference (1 RCT, N = 228, RR 1.01, 95% CI 0.93 to 1.09, high-quality evidence). There was a clear demonstration of reduced risk of needing additional medication after 60 minutes for participants in the droperidol group (2 RCTs, N = 255, RR 0.37, 95% CI 0.16 to 0.90, high-quality evidence). There was no evidence that droperidol caused more cardiovascular hypotension (1 RCT, N = 228, RR 2.80, 95% CI 0.30 to 26.49,moderate-quality evidence) and cardiovascular hypotension/desaturation (1 RCT, N = 228, RR 2.80, 95% CI 0.12 to 67.98, low-quality evidence) than haloperidol. There was no suggestion that use of droperidol was unsafe. For mental state, there was no evidence of clear difference between the efficacy of droperidol compared to haloperidol (Scale for Quantification of Psychotic Symptom Severity, 1 RCT, N = 40, mean difference (MD) 0.11, 95% CI -0.07 to 0.29, low-quality evidence). There were no data for service use and costs.Whereas, when droperidol was compared with midazolam, for the outcome of tranquillisation or asleep by 30 minutes we found droperidol to be less acutely tranquillising than midazolam (1 RCT, N = 153, RR 0.96, 95% CI 0.72 to 1.28, high-quality evidence). As regards the 'need for additional medication by 60 minutes after initial adequate sedation, we found an effect (1 RCT, N = 153, RR 0.54, 95% CI 0.24 to 1.20, moderate-quality evidence). In terms of adverse effects, we found no statistically significant differences between the two drugs for either airway obstruction (1 RCT, N = 153, RR 0.13, 95% CI 0.01 to 2.55, low-quality evidence) or respiratory hypoxia (1 RCT, N = 153, RR 0.70, 95% CI 0.16 to 3.03, moderate-quality evidence) - but use of midazolam did result in three people (out of around 70) needing some sort of 'airway management' with no such events in the droperidol group. There were no data for mental state, service use and costs.Furthermore, when droperidol was compared to olanzapine, for the outcome of tranquillisation or asleep by any time point, we found no clear differences between the older drug (droperidol) and olanzapine (e.g. at 30 minutes: 1 RCT, N = 221, RR 1.02, 95% CI 0.94 to 1.11, high-quality evidence). There was a suggestion that participants allocated droperidol needed less additional medication after 60 minutes than people given the olanzapine (1 RCT, N = 221, RR 0.56, 95% CI 0.36 to 0.87, high-quality evidence). There was no evidence that droperidol caused more cardiovascular arrhythmia (1 RCT, N = 221, RR 0.32, 95% CI 0.01 to 7.88, moderate-quality evidence) and respiratory airway obstruction (1 RCT, N = 221, RR 0.97, 95% CI 0.20 to 4.72, low-quality evidence) than olanzapine. For 'being ready for discharge', there was no difference between groups (1 RCT, N = 221, RR 1.06, 95% CI 0.83 to 1.34, high-quality evidence). There were no data for mental state and costs.

Previously, the use of droperidol was justified based on experience rather than evidence from well-conducted and reported randomised trials. However, this update found high-quality evidence with minimal risk of bias to support the use of droperidol for acute psychosis. Also, we found no evidence to suggest that droperidol should not be a treatment option for people acutely ill and disturbed because of serious mental illnesses.