At Visit 2, subjects continuing to meet eligibility criteria will be randomized 1:1 to Treximet or naproxen and provided with medication to treat daily for 30 days. At Visits 3 and 4 subjects will be provided with study medication to treat on 14 or fewer days per month. Subjects will be encouraged to treat their migraine attacks within 1 hour of onset of headache pain and while the pain is still mild. Adverse events will be collected beginning from the first dose of study medication. Subjects exit the study at Visit 5 after a 3-month Treatment Period.