Feverfew is the fresh or dried leaf of a member of the aster family native to the Balkan peninsula. It is naturalized in Europe, as well as in North and South America.
The English herbalist Nicholas Culpeper (1787) wrote that feverfew "is very effectual for all pains in the head coming of a cold cause, the herb being bruised and applied to the crown of the head." For more than 2,000 years, feverfew was a folk medicine taken internally for fevers, headache, or menstrual regulation, or applied externally to relieve pain.
Modern use focuses on feverfew to help prevent migraines. A compound called parthenolide (not found in all feverfew varieties) appears to be responsible for its antimigraine effects.
During the past decade, clinical interest in feverfew increased after an English newspaper asked for volunteers with experience in using feverfew for migraines and received 25,000 replies. Of three hundred volunteers, 70 percent claimed a reduction in migraine frequency or pain after eating one to three fresh leaves a day. In a 1985 doubleblind study conducted by London researchers, seventeen patients ingested an average daily dose of 60 mg of feverfew leaves and experienced no change in frequency or severity of migraine symptoms. Those who took the placebo, however, had an increase in frequency and severity of headaches, nausea, and vomiting.
In a 1988 randomized, double-blind, placebo-controlled, crossover study on feverfew in migraine prevention in Nottingham, seventytwo volunteers received either a feverfew capsule or a placebo daily for four months. The feverfew treatment was associated with a reduction in frequency of migraine headaches and related vomiting as well as some reduction in migraine severity; the duration of migraine attacks was not significantly shortened.
The fresh leaves, dried leaves, capsules standardized to parthenolide content, tablets, and tinctures are available in the American market. Canadian authorities have adopted a 0.2 percent parthenolide content as a minimum standard for feverfew products.
No long-term studies have been done on safety. Mouth ulcers have been reported in 7 to 12 percent of patients who chewed the fresh leaves; tongue inflammation, swelling of the lips, and occasional loss of taste sometimes prevent continued use. These symptoms disappear when use is stopped. Avoid during pregnancy.