Comparison of efficacy and frequency of akathisia and dystonia between olanzapine, metoclopramide and prochlorperazine in ED headache patients

Study objective: To compare the efficacy and frequency of akathisia and dystonia between the dopamine antagonist headache medications olanzapine, metoclopramide and prochlorperazine. Methods: This was a retrospective observational cohort study of patients presenting to a large urban level one trauma center between 2010 and 2018. Inclusion criteria was age ≥ 18 who presented to the emergency department with a chief complaint of headache who received either olanzapine, metoclopramide or prochlorperazine. The primary outcome was need for rescue medication. Secondary outcomes were receiving medication for either akathisia or dystonia. Logistic regression was used to identify differences between the three cohorts up to 72 h from initial presentation. Results: There were 5643 patients who met inclusion criteria. Olanzapine was the most commonly used drug (n = 2994, 53%) followed by prochlorperazine (n = 2100, 37%) and metoclopramide (n = 549, 10%). After adjusting for age and gender, there were no differences in risk for receiving rescue therapy or developing akathisia or dystonia. Conclusion: During initial ED visit and up to 72 h after receiving olanzapine, metoclopramide or prochlorperazine, we found no difference in risk for requiring rescue medication or developing akathisia or dystonia.