A 25-year-old female has a history of a subarachnoid hemorrhage 3 years earlier, which was caused by a middle cerebral aneurysm. The aneurysm was successfully coiled, with no aneurysms seen on follow-up angiography. She had a full neurologic recovery with no residual neurological deficits. On exam, she has no focal neurological deficits. She has no family history of aneurysms. She is now seeking medical advice for her migraine headaches, with and without aura, which occur once every few months. She has tried over-the-counter analgesics without much benefit. Which of the following is the most appropriate management of this patient?