Comparison of the Effectiveness of Haloperidol Injection and Oral Quetiapine to Control Delirium in Patients in the Emergency Department and Intensive Care Unit – A Randomized Clinical Trial

Background: Delirium is a psychiatric syndrome observed among patients with critical psychiatric disorders. Haloperidol is now one of the first-line drugs for the treatment of delirium. However, quetiapine can be considered as an appropriate substitute in patients with a high risk of extrapyramidal symptoms or long QT syndrome. Objectives: This study aimed to compare the effectiveness of intramuscular haloperidol and oral quetiapine to control delirium in patients in the emergency department and intensive care unit. Methods: This randomized clinical trial was performed during 2017-2018 on patients with delirium who were referred to the emergency department and intensive care unit of Imam Reza Hospital (referral center), Mashhad, Iran. Patients were divided into two groups of 100 patients per group through a random allocation technique . In this study, 5 mg of intramuscular haloperidol every 12 hours and  25 mg of oral quetiapine were prescribed daily for the patients in the control and intervention groups, respectively. The delirium severity score of each patient was evaluated before and three days after the intervention through Delirium Rating Scale-Revised-98. Results: In this study, the mean±SD age of participants was 60.2±14.1 years. The findings indicated that no significant difference was observed between haloperidol (22.7±1.9) and quetiapine (22.7±2.2) groups in terms of the baseline delirium severity score (P=0.95). The mean delirium severity scores of patients in haloperidol and quetiapine groups were 25.6±2.1 and 25.2±2.5, respectively. Based on the obtained results, the difference between the delirium severity scores of both groups was not statistically significant (P=0.24). Conclusion: Based on the results, oral quetiapine has a similar effect as intramuscular haloperidol and can be used as a substitute to this medicine for controlling the symptoms of patients with delirium.