A deficit of mitochondrial energy metabolism may play a role in
migraine pathogenesis. We found in a previous open study that high-dose
riboflavin was effective in
migraine prophylaxis. We now compared
riboflavin (400 mg) and placebo in 55 patients with
migraine in a randomized trial of 3 months duration. Using an intention-to-treat analysis,
riboflavin was superior to placebo in reducing attack frequency (p = 0.005) and
headache days (p = 0.012). Regarding the latter, the proportion of patients who improved by at least 50%, i.e. "responders," was 15% for placebo and 59% for
riboflavin (p = 0.002) and the number-needed-to-treat for effectiveness was 2.3. Three minor adverse events occurred, two in the
riboflavin group (
diarrhea and
polyuria) and one in the placebo group (
abdominal cramps). None was serious. Because of its high efficacy, excellent tolerability, and low cost,
riboflavin is an interesting option for
migraine prophylaxis and a candidate for a comparative trial with an established prophylactic
drug.