Picture the feverfew commercial. Someone grimacing and obviously uncomfortable. Headache! But in thirty seconds and with a little feverfew powder, they're all smiles and having fun. As it runs there's a very rapidly spoken and not very loud voice over, "Long term use of feverfew followed by abrupt termination may induce a withdrawal syndrome featuring rebound headaches and muscle and joint pains. Feverfew may cause allergic reactions, including contact dermatitis. Other side effects have included gastrointestinal upset such as nausea, vomiting, abdominal pain, diarrhea, and flatulence. When the herb is chewed or taken orally it can cause mouth ulcers and swelling and numbness of the mouth. Feverfew should not be taken by pregnant women. It may interact with blood thinners and increase the risk of bleeding, and may also interact with a variety of medications metabolized by the liver (from Wikipedia)." So buy some from Amazon for $19.95, or enjoy it blooming wild in AL, CA, CO, CT, DE, HI, ID, IL, IN, KY, MA, MD, ME, MI, MN, MO, MS, MT, NC, NH, NJ, NV, NY, OH, OR, PA, RI, SC, UT, VA, WA, WI, WV, WY, BC, MB, NB, NF, NS, ON, PE, and QC. Or grab some aspirin, also a traditional herbal remedy. Beal Gardens MSU, 6/24/12. Aster family, Asteraceae.