Facilitators of Change - USDA

For headache sufferers, caffeine is a double-edged sword. On the one hand, small amounts of caffeine constrict blood vessels -- which makes it useful in controlling migraine. In fact, caffeine is an active ingredient in several migraine drugs. But too much caffeine (more than 2 or 3 cups a day) can make a headache worse, or even bring one on. ................
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