DOUBLE-BLIND-STUDY OF INTRAVENOUS ASPIRIN VS PLACEBO IN THE TREATMENT ACUTE MIGRAINE ATTACKS

Introduction The empirical use of oral acetylsalicylic acid (ASA) in the treatment of acute migraine attacks has led to the recommendation of ASA as a basic treatment of migraine. However, there are no controlled studies on the intravenous use of acetylsalicylic acid. Methods Forty patients with a 1- to 12-year history of migraine were included in this placebo-controlled trial. The sociodemographic data of patients receiving placebo or 500 mg ASA i.v. and migraine symptoms before treatment were identically distributed. Pain relief during attacks was documented by the Visual Analogue Scale (VAS) for 1 h at 5-min intervals. Furthermore, the change of concurrent non-pain symptoms was evaluated by self-rating (worse - unchanged - better absent). Results The VAS showed a mean pain reduction of about 60 % after 1 h versus placebo. Efficacy varied significantly between patients. We observed a small number of so-called non-responders as well as patients with complete pain relief. The most common concomitant symptoms were nausea, photophobia, vertigo, Vomiting and sweating. During the time of observation these symptoms were significantly reduced compared to placebo. The study shows a maximum placebo effect of about 17 % (mean value). Significant differences in pain ratings were measured 25-30 min after application (P = 0.0008). Conclusions In this study i. v. ASA showed a significant reduction in pain intensity during migraine attacks. In addition, most concomitant non-pain symptoms were equally reduced. The onset of pain relief did not correspond with the inhibition of platelet aggregation (after 24 min) or with peak plasma concentrations of ASA (immediately after application) or salicylic acid (after 2-3 h). More efficacy studies with higher doses and longer periods of observation are necessary to optimize the treatment of migraine attacks with intravenous ASA. Studies including neurophysiological and vascular parameters are recommended to confirm the results of this study.