In a multicentric, open, preliminary trial, we evaluated the use of ginkgolide B, a herbal constituent extract from Ginkgo biloba tree leaves, in the prophylactic treatment of migraine with aura (MA). Fifty women suffering from migraine with typical aura, or migraine aura without headache, diagnosed according to International Headache Society criteria, entered a six-month study. They underwent a two month run-in period free of prophylactic drugs, followed by a four month treatment period (subdivided into two bimesters, TI and TII) with a combination of 60 mg ginkgo biloba terpenes phytosome, 11 mg coenzyme Q 10, and 8.7 mg vitamin B2 (Migrasoll), administered twice daily. A detailed diary reporting neurological symptoms, duration, and frequency of MA was compiled by patients throughout the trial. The number of MA significantly decreased during treatment (from 3.7 +/- 2.2 in the run-in period, to 2.0 +/- 1.9 during TI and to 1.2 +/- 1.6 during TII; Anova for repeated measures: P < 0.0001). There was also a statistically significant decrease in the average MA duration, which was 40.4 +/- 19.4 min during run-in, 28.2 +/- 19.9 during TI, and 17.6 +/- 20.6 during TII. Total disappearance of MA was observed in 11.1% patients during TI and in 42.2% of patients during T2. No serious adverse event was provoked by Migrasoll administration. Ginkgolide B is effective in reducing MA frequency and duration. The effect is clearly evident in the first bimester of treatment and is further enhanced during the second.