From my studies Feverfew benefits ~2/3s of the people who try it for migraines. Because it contains parthenolides, compounds that seem to inhibit the release of serotonin from platelets. This is how it prevents constiction of brain arteries. The dosage recommended is up to three 300 to 400 mg. caps QD. The plant tastes very bitter so may benefit from sticking to the caps.
One caution: Do not use during pregnancy. Just a P.S.- if you want to use it as a tea, best results are obtained by using the whole plant - the fresher the better. Fresh leaf extracts blocked constriction, which is desirable. But dried leaf extracts caused contractions

If you choose to eat the leaves they have been found to cause mouth sores in some people. You certainly can try it as a tea though, if you don't mind the taste.
You may wish to use Bay (laurus nobilis) in conjunction with feverfew. Bay also contains parthenolides, and is recommended by James Duke, PhD (author of The Green Pharmacy.) Typical dose is not well established, so you might want to check with the practitioner (?clerk at the store you get the herbs at.)
Another idea to consider is that it has been shown that many people who have migraines have either food allergies or food intolerances, which may not be picked up with standard allergy tests.
Big offenders are: cow's milk, wheat, chocolate, eggs, citrus fruits, strawberries, cheese, tomatoes, rye and the food additives tartrazine and benzoic acid.
Others could be red wine, caffeinated beverages, processed meats, MSG and aspartame (Nutrasweet). You'd have to try an elimination diet if you suspect these could be a culprit.
Hope this info helps
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