DOES IT WORK?Migraine is a common, debilitating condition that may not respond to pharmaceuticals
FEVERFEW IS often found in old gardens because of its relatively large, daisy-like flowers. While its name comes from its use in treating fevers, it has been heralded more recently as a remedy to prevent migraine headaches.
Migraine is a relatively common, recurrent problem which can be severely debilitating. Migraines and tension headaches can be caused by a variety of different factors, including foods, environmental factors and sleep disorders.
In treating and preventing migraines, such lifestyle factors must be considered. Pharmaceutical drugs are available, but can have adverse effects. Feverfew is promoted by some as a mild and safe remedy for the prevention of migraines.
Evidence from studies
At least 40 different chemicals have been isolated from feverfew and shown to have some biological effect. Parthenolide was assumed to be the ingredient active against migraine, but recent studies have raised questions about this.
Several of the ingredients influence hormones and chemicals found in the brain, which lends credence to feverfew's potential impact on migraines. However, no consensus exists regarding how feverfew might prevent migraines.
About half a dozen controlled trials have been carried out using feverfew to prevent migraine. The longest lasted only four months. The results have been mixed.
Of the trials which showed no benefit from feverfew, most used an extract of the plant, but also were the trials of highest quality. The trials which found feverfew beneficial were of lower quality, and used the dried plant material in capsules.
The migraine patients who received feverfew tended to have fewer numbers of migraine headaches, but only one study found that the headache severity was reduced. Most of the evidence does not support feverfew improving migraine symptoms once an attack commences.
Controlled trials have not been conducted to test if feverfew is helpful in the treatment of migraines. All of the research located tested it as a means of preventing migraine.
Problematic aspects
When taken in capsule form, adverse effects are relatively uncommon and mostly gastrointestinal problems. Traditionally, people were recommended to chew fresh feverfew leaves. This can lead to mouth ulcers, swollen tongue and lips and loss of taste.
These adverse effects have also been reported in some people using capsules containing dried plant material.
Feverfew is a member of the aster and daisy family, so anyone who is allergic to such plants (including chrysanthemums and marigolds) should be cautious when first trying feverfew.
Quality control appears to be difficult with feverfew products. Some of the active ingredients are unstable, and their concentration in the plant varies widely depending on the time of the year.
When independent researchers have tested commercial products, large variations have been found in the amount of active ingredient they contain.
Recommendations
Migraine is a relatively common and debilitating condition.
While pharmaceuticals are available to prevent and treat migraines, they can have problematic side effects and don't work well for some migraine sufferers.
Some people with recurring migraine headaches might receive some benefit from feverfew.
However, the evidence available to support this is not particularly strong.
Feverfew is relatively safe, although care should be taken at first to watch for allergic reactions and mouth sensitivity. The evidence is slightly stronger for using products that contain dried plant material rather than extracts of the plants.
To reduce the incidence of migraine, other lifestyle factors such as diet, sleep and stress reduction should be examined. Once a migraine begins, however, there is no evidence that feverfew will reduce its duration or severity.
Conventional treatments should be pursued at that point.
• Dónal OMathúna has a PhD in pharmacy, researching herbal remedies, and an MA in bioethics, and is a Senior Lecturer in the School of Nursing, Dublin City University. He authored Alternative Medicine: The Christian Handbook, Updated and Expanded Edition, Zondervan, 2007