Background: To investigate the efficacy and safety of supplementation with a fixed combination of magnesium, vitamin B2, feverfew, andrographis paniculata and coenzyme Q10 in episodic migraine (EM) prevention. Methods: A pilot, single-arm, open-label study was conducted. After a one-month baseline period, the above-described supplementation was introduced in 113 EM Greek patients, who were prospectively followed-up for three months. The primary endpoint was the change in monthly migraine days between baseline period (BSL) and the third month of supplementation (T3). Secondary endpoints included changes in mean intensity of migraine and in days with use of acute migraine medications. Changes in scores of Migraine Disability Assessment questionnaire (MIDAS), Headache Impact Test-6 (HIT-6), Migraine Therapy Assessment questionnaire (MTAQ), Migraine-Specific Quality-of-life questionnaire (MSQ-QOL), Hospital Anxiety and Depression Scale (HADS) were also evaluated. Those with ≥50% reduction in monthly migraine days at T3, compared to BSL were considered supplementation-responders. Results: The mean number of migraine days was significantly decreased between BSL and T3 (9.4 ± 3.7 vs. 6.1 ± 3.5; p < 0.001). Likewise, days with peak headache intensity of >4/10 (5.7 ± 3.4 vs. 4.9 ± 3.1; p < 0.001) as well as days using acute headache medications per month (8.9 ± 3.6 vs. 5.7 ± 3.4; p < 0.001) were significantly reduced. At T3, 64 patients (56.6%) were classified as responders. The beneficial effect of supplementation was also associated with significant changes in HIT-6, MIDAS, MTAQ and MSQ-QOL scores. There were no safety concerns. Conclusions: The supplementation we have tested appears to be an effective and well-tolerated preventive approach against EM. A randomized, placebo-controlled study is needed to confirm our results.