Davis et al Cytoskeletal Signaling inhibitor compared ketorolac 60 mg IM with promethazine 25 mg IM plus meperidine 75 mg IM and found that there was no difference between the 2 groups in percentage pain free at 30 minutes (promethazine/meperidine 20.8% vs ketorolac 22.3%).7 Harden et al found no difference in headache relief between ketorolac 60 mg IM (44.4%), meperidine 50 mg plus promethazine 25 mg IM (60%), or placebo/NS IM (54.5%).9 Duarte et al found no difference in pain reduction (VAS) for

ketorolac 60 mg IM compared with meperidine 100 mg IM plus hydroxyzine 50 mg IM (−33.5 vs −33.7, P = .76); the percentage complaining of nausea and drowsiness was not significantly less for ketorolac (28% vs 48%, P = .15).8 Larkin and Prescott compared ketorolac 30 mg IM with meperidine 75 mg IM; the percentage pain free at 1 hour was greater for meperidine (30% vs 6%, P < .05), as was sustained pain freedom at 24 hours (44% vs 13%, P < .02), and no adverse events were reported in either group.11 Klapper and Stanton found that ketorolac 60 mg IM was less effective in treating migraine than DHE 1 mg IV plus metoclopramide 5 mg IV; headache relief (4-PPS) at 1 hour was greater for DHE/metoclopramide (78% vs 33%, P = .031).22 Bigal et al compared metamizole (MMZ, also called dipyrone and not available in the USA) 1000 mg IV with placebo/NS buy IWR-1 IV.23 For migraineurs without aura, pain reduction (11-PPS) with

MMZ was more effective than placebo at 30 and 60 minutes (−4.0 vs −1.2, P < .01 and −6.0 vs −3.0, P < .01). For patients with aura, the reduction was also significantly greater with MMZ at 30 and 60 minutes (−4.9 vs −0.9, P < 0.01 and −6.4 vs −1.9, P < .01). Krymchantowski et al then compared MMZ 1000 mg IV with lysine clonixinate (LC, an NSAID not available in the USA) 200 mg IV, delivered as a 25 mL infusion over 5 minutes.24 The percentage pain free at 60 and 90 minutes was greater with LC (60 minutes: 33% vs 13%, P < .001; 90 minutes: 86.7% vs 73%, P < .001). There was no follow-up post-discharge. Patients receiving

LC had more injection-site pain than those receiving MMZ (13/15 vs 3/15, P < .0001). Engindeniz et al compared diclofenac sodium 75 mg IM with tramadol 100 mg IM. Headache relief at 2 hours was the same for both groups (80%).16 Ellis et al 上海皓元 compared ibuprofen 600 mg oral (PO) with metoclopramide 10 mg IV and placebo; pain reduction (VAS) was similar for metoclopramide and metoclopramide/ibuprofen (−75 vs −50) but was greater in both these groups (P < .01) than in the ibuprofen or placebo groups, which were the same (−25).25 Table 2 summarizes the studies involving ketorolac, diclofenac, ibuprofen, LC, and MMZ (the last not an NSAID). The rate of headache recurrence within 24-72 hours following discharge from the ED can exceed 50%, and corticosteroids typically are used in the ED in an attempt to reduce the frequency of such recurrence.