does not cause the migraine, but it increases the pain associated with the migraine.) Because the purr reduces swelling and inflammation, it can help the blood vessels to fully open, and reduce the pain of a migra⦠the mismatch does not cause the migraine, but it increases the pain associated with the migraine.) Because the purr reduces swelling and inflammation, it can help the blood vessels to fully open, and reduce the pain of a migraine.