Prochlorperazine is more effective than ketamine for relief of benign headaches in patients admitted to the emergency department, according to findings published in the Annals of Emergency Medicine.

Investigators performed a double-blind randomized placebo-controlled trial to evaluate the outcomes of prochlorperazine (n=29) vs ketamine plus ondansetron (n=25) in patients admitted to the emergency department for benign headaches (N=54). The visual analog scale (VAS) was used to determine headache severity at specific time intervals.

Based on the VAS, the investigators found that patients receiving prochlorperazine had a greater reduction in headache-related pain compared with patients receiving ketamine (56.1 mm vs 38.0 mm, respectively; 95% CI, 1.0-35.2 mm).

Continue Reading

At 60 minutes after the intervention, the arm receiving prochlorperazine experienced an average VAS improvement of 63.5mm vs 43.5 mm in patients treated with ketamine. Overall, there was a between-groups difference of 20.0 mm (95% CI, 2.8-37.2 mm; P =.026).

The average satisfaction score for prochlorperazine was numerically higher than ketamine (8.3 vs 4.9; 95% CI, 1.2-5.6). No significant difference was observed between groups in regard to the frequency of headaches at follow-up or in secondary outcomes.

Related Articles

In this study, patients were enrolled only in the event that an emergency department pharmacist was available for therapy, potentially limiting the study’s findings. In addition, the investigators noted that the small sample size, as well as the study’s early termination, weakened the power of the findings.

Although the results of this trial “strongly suggest the superiority of prochlorperazine over ketamine for headaches,” the investigators noted that ketamine may still be beneficial in patients with headaches admitted to the emergency department.


Zitek T, Gates M, Pitotti C, et al. A comparison of headache treatment in the emergency department: prochlorperazine sersus ketamine [published online October 13, 2017]. Ann Emerg Med. doi:10.1016/j.annemergmed.2017.08.063