All 4 studies comparing prochlorperazine to placebo favored prochlorperazine over placebo regardless of the route of delivery (PR, IM, and IV). In the 2 conflicting studies comparing chlorpromazine to placebo, one found chlorpromazine to be clearly superior to placebo, but in the second study, it outperformed placebo only in terms of a reduced need for rescue medication. Prochlorperazine outperformed ketorolac, magnesium, valproate, octreotide, and sumatriptan. Among the neuroleptics, prochlorperazine was more rapidly effective than promethazine and superior to metoclopramide

as a single agent in providing pain relief. When Y-27632 chemical structure prochloperazine and metoclopramide were combined with diphenhydramine in a separate study, there was no difference in efficacy. Chlorpromazine was superior to meperidine, DHE, and lidocaine, and similar to sumatriptan

in pain relief. No studies directly compared prochlorperazine to chlorpromazine. In every investigation of the efficacy of promethazine IM, it was combined with meperidine. As a combination therapy, it performed on par with ketorolac, DHE plus metoclopramide, and placebo. Promethazine should not be administered IV or SQ due to the risk of severe tissue injury, including gangrene. Methotrimeprazine, as a single agent, was similar in selleckchem pain relief to meperidine plus dimenhydrinate. Adding a small dose of prochlorperazine (3.5 mg) to DHE did not boost pain relief, but it did decrease the side effect of nausea (albeit with some increase in the incidence of sedation and a minimal increase in akathisia). The most commonly reported adverse events for prochlorperazine were drowsiness (15-18%) and akathisia, sometimes severe (8-46%). For chlorpromazine, the common

side effects were drowsiness (70%) and postural hypotension (17-53%), and for methotrimeprazine, drowsiness (52%) was the side effect most commonly reported. Chlorpromazine has some anticholinergic medchemexpress activity that can counteract akathisia. The percentage pain-free at 2 hours was greater for droperidol (∼40%) than placebo (∼20%). Both studies comparing droperidol to prochlorperazine resulted in greater pain relief with droperidol, but in 1 study, there was no difference in average pain reduction. No patients given droperidol exhibited QT prolongation, but they did experience anxiety (30%), akathisia (6-13.3%), and drowsiness (6.7-30%). The 1 study comparing haloperidol to placebo showed superior headache relief with haloperidol (80% vs 15%). Sedation and akathisia were reported in 53% of patients taking haloperidol. Because of black box warnings for prolonged QTc and the common side effects of sedation and akathisia, droperidol and haloperidol should be reserved for use only when other rescue medications fail to relieve headache. Checking the QTc with an ECG before and after treatment, pretreatment with diphenhydramine, trihexyphenidyl, benztropine, or a benzodiazepine and IV fluids all are recommended.