Using herbs to treat migraines requires continual use, i.e you are trying to prevent migraines or reduce frequency, intensity or duration. Taking them once you have a migraine is not very effective. The only exception would be someone who only gets a migraine twice per year, and then treating them daily is not necessary and you would try to determine any triggers (weather, humidity, foods, stress, etc) avoid them if possible and treat at the earliest sign of an impending migraine.