I am not too sure on this subject and don't get migraines but a mate of mine has them regularly, he says he sometimes gets this feeling too... Sometime there is a high pitched buzzying in his head and he starts to feel dizzy and the room spins. Other times he will vomit, and/or sleep through the day and be awake all night but as you said, the tablets will take effect, but will wear off after a period of time... Hope this helps you with what you are trying to understand x x
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