What Is Feverfew Used for Today?

Feverfew is primarily used for the prevention of migraine headaches. For this purpose, it is taken daily. There has been no formal investigation of feverfew as a treatment for migraines that have already started, although one double-blind study evaluating feverfew as a preventive agent did find hints of possible symptom-reducing benefits.¹²

It is important to remember that serious diseases may occasionally first present themselves as migraine-type headaches. For this reason, proper medical diagnosis is essential if you suddenly start having migraines without a previous history, or if the pattern of your migraines changes significantly.

Feverfew is sometimes recommended for osteoarthritis or rheumatoid arthritis, but there is no evidence at all that it works.

What Is the Scientific Evidence for Feverfew?

Five meaningful double-blind, placebo-controlled studies have been performed to evaluate feverfew's effectiveness as a preventive treatment for migraines. The best of the positive trials used a feverfew extract made by extracting the herb with liquid carbon dioxide. Two other trials that used whole feverfew leaf also found it effective; however, two studies that used feverfew extracts did not find benefit.

In a well-conducted 16-week, double-blind, placebo-controlled study of 170 people with migraines, use of a feverfew extract at a dose of 6.25 mg 3 times daily resulted in a significant decrease in headache frequency as compared to the effect of the placebo treatment.²² In the treatment group, headache frequency decreased by 1.9 headaches per month, as compared to a reduction of 1.3 headaches per month in the placebo group. The average number of headaches per month prior to treatment was 4.76 headaches. The extract used in this study was made utilizing liquid carbon dioxide.

A previous study using the same extract had failed to find benefit, but it primarily enrolled people with less frequent migraines.¹²

Two other studies used whole feverfew leaf and found benefit. The first followed 59 people for 8 months.⁹ For 4 months, half received a daily capsule of powdered feverfew leaf; the other half took placebo. The groups were then switched and followed for an additional 4 months. Treatment with feverfew produced a 24% reduction in the number of migraines and a significant decrease in nausea and vomiting during the headaches. A subsequent double-blind study of 57 people with migraines found that use of feverfew leaf could decrease the severity of migraine headaches.¹⁰ Unfortunately, this trial did not report whether there was any change in the frequency of migraines; it is possible, therefore, that this study actually showed a symptom-reducing effect rather than a preventive benefit.

One study using an alcohol extract failed to find benefit.¹¹

Some migraine sufferers experience a mild headache before the onset of their full blown migraine. A randomized trial involving 60 such patients found that a sublingual (placed under the tongue for rapid absorption) combination of feverfew and ginger taken at the onset of this early headache helped to reduce or eliminate pain for at least 2 hours.²³

Dosage

The tested liquid-carbon-dioxide feverfew extract is taken at a dose of 6.25 mg 3 times daily. To replicate the dosage of feverfew used in the two positive studies of whole leaf described above, take 80 to 100 mg of powdered whole feverfew leaf daily.

Safety Issues

Animal studies suggest that feverfew is essentially nontoxic.¹³ In one 8-month study, there were no significant differences in side effects between the treated and control groups.¹⁴ There were also no changes in measurements on blood tests and urinalysis.

In a survey involving 300 people, 11.3% reported mouth sores from chewing feverfew leaf, occasionally accompanied by general inflammation of tissues in the mouth.¹⁵ A smaller percentage reported mild gastrointestinal distress.¹⁶ However, mouth sores do not seem to occur in people who use encapsulated feverfew leaf powder, the usual form.

In view of its use as a folk remedy to promote abortions, feverfew should probably not be taken during pregnancy.

Because feverfew might slightly inhibit the activity of blood-clotting cells known as platelets,¹⁷ it should not be combined with strong anticoagulants, such as warfarin (Coumadin) or heparin, except on medical advice. Feverfew might also increase the risk of stomach problems if combined with anti-inflammatory drugs, such as aspirin.^18,19,20

Safety in young children, pregnant or nursing women, or those with severe kidney or liver disease has not been established.

Interactions You Should Know About

If you are taking:

• Warfarin (Coumadin), heparin, aspirin, or other nonsteroidal anti-inflammatory drugs: Do not use feverfew except on medical advice.