Olanzapine versus droperidol for the treatment of primary headache in the emergency department

Objectives: The objective was to determine if there is a difference in pain relief or frequency and severity of side effects in emergency department (ED) patients with primary headache treated with either intramuscular (IM) olanzapine or IM droperidol. Methods: This was a prospective, randomized nonblinded clinical trial of adult ED patients undergoing treatment for suspected primary headache. Consenting patients were randomized to receive either droperidol 5 mg IM or olanzapine 10 mg IM. Prior to receiving treatment, patients were asked to complete a 100-mm visual analog scale (VAS) describing their pain and a 4-point verbal rating scale (VRS) describing their pain as none, mild, moderate, or severe. Patients also completed a 100-mm VAS describing their level of nausea. Pain and nausea measurements were repeated 30 and 60 minutes after medication administration. Patients also completed the Barnes Akathisia Scale (BAS) 30 and 60 minutes after medication administration. Descriptive statistics were used as appropriate. Pain relief was compared both in terms of the decrease in VAS scores and in the proportion of patients who reported moderate or severe pain whose report later changed to mild or no pain. Results: One-hundred patients were enrolled; 13 were withdrawn before administration of the study medication, 8 in the droperidol group and 5 in the olanzapine group, leaving 87 patients for analysis. Forty-two patients received droperidol and 45 received olanzapine. In the droperidol group, 35/40 (87.5%) patients who had reported moderate or severe pain at baseline reported mild or no pain at 60 minutes. In the olanzapine group, 38/44 (86.4%) reported this change (p = 0.89). The mean percent change from baseline VAS pain score at 60 minutes was -37% (95% CI = -84% to 11%) for droperidol and -37% (95% CI = -64% to 10%) for olanzapine (p = 0.30). The mean percent change from baseline for the VAS nausea score was -59% (95% CI = -70% to -47%) for droperidol and -64% (95% CI = -77% to -51%) for olanzapine (p = 0.83). There was no difference in any report of akathisia by the BAS between the groups (p = 0.63). Conclusions: Both olanzapine and droperidol are effective treatments for primary headaches in the ED. No significant differences were found between the medications in terms of pain relief, antiemetic effect, or akathisia. Olanzapine may be used to treat primary headache and it is an effective alternative to droperidol.