Feverfew (Tanacetum parthenium), a member of the sunflower family, has been used for centuries in European folk medicine as a remedy for headaches, arthritis, and fevers. In fact, the term feverfew is adapted from the Latin word febrifugia or fever reducer. Feverfew has also been traditionally used to treat menstrual irregularities, labor difficulties, skin conditions, stomach aches, and asthma. Today, professional herbalists primarily use feverfew to treat and prevent certain headaches, arthritis, and other painful disorders. Studies evaluating the scientific validity of these uses of feverfew, however, have elicited some debate. See the discussions that follow about migraines and arthritis respectively.

Migraine Headaches
Feverfew gained popularity in Great Britain in the 1980s as an alternative to conventional medications for migraine headaches. In fact, a survey of 270 migraine sufferers in Great Britain revealed that more than 70% of individuals felt substantially better after ingesting an average of two to three fresh feverfew leaves daily. Since then, several well-designed studies have been conducted to evaluate the safety and effectiveness of feverfew for the prevention and treatment of migraine headaches. Most of these studies have found beneficial results. For example, in a study of 76 migraine sufferers, those who ingested feverfew capsules (70 to 114 mg) daily for 4 months experienced a 24% reduction in attacks and a substantial drop in symptoms that often accompany migraines, such as nausea and vomiting, compared to those who received placebo.

Despite such positive findings, some experts have questioned the quality of these studies. Two recent critical reviews of studies on feverfew for migraine headaches conducted to date draw slightly different conclusions. One group of experts concluded that feverfew appears to be beneficial for the prevention of migraine headaches, but that scientific studies on this topic have been poorly designed to date, making it difficult to draw any firm conclusions until better-designed studies are conducted. The other team of experts states, upon conclusion, that "feverfew is likely to be effective in the prevention of migraine."

Again, many individuals have had success working with an herbal specialist to control their migraines by using feverfew. It is particularly important when using feverfew to do so with guidance from a specialist because there is wide variability in the formulations of this herb sold over the counter. This may explain why some studies show improvement in migraines while others do not.

For now, some suggest that feverfew may be most appropriate for migraine sufferers who have not gotten better using conventional therapies or cannot tolerate standard medications due to side effects. Other specialists point out that many prescription medications used for headaches do not have the strongest data to support their use either. They go on to say that given that feverfew has fewer side effects and greater tolerability, this herb is definitely an important option for people with migraines.

Arthritis
Although many laboratory tests demonstrate anti-inflammatory properties of feverfew and many professional herbalists recommend feverfew for the treatment of arthritis, a study conducted in 1989 concluded that feverfew was no more effective than placebo in improving symptoms of rheumatoid arthritis. Some experts argue that this study was poorly designed, particularly because some patients continued, throughout the study, to use non-steroidal anti-inflammatory drugs (NSAIDs), which can interfere with feverfew and reduce its effectiveness. (NSAIDs, such as ibuprofen, are commonly prescribed or recommended for arthritis.) Until further studies are conducted, it appears that the safety and effectiveness of feverfew in people with rheumatoid arthritis has yet to be scientifically proven.

Native to southeastern Europe, feverfew is now widespread throughout Europe, North America, and Australia. Feverfew is a short perennial that blooms between July and October. This aromatic plant gives off a strong and bitter odor. Its yellow-green leaves are alternate (which means that the leaves grow on both sides of the stem at alternating levels), and turn downward with short hairs. The small, daisy-like yellow flowers are arranged in a dense flat-topped cluster.

Feverfew products usually consist of dried feverfew leaves, but the aerial parts of the plant (all parts of the plant that grow above ground) may also be used for medicinal purposes. The migraine-relieving activity of feverfew is believed to be due to parthenolide, an active compound that helps relieve smooth muscle spasms. In particular, it helps prevent the constriction of blood vessels in the brain (one of the leading causes of migraine headaches). Parthenolide also inhibits the actions of compounds that cause inflammation.

Feverfew is available fresh or dried (for use in teas), or can be purchased in capsule, tablet, and liquid extract forms. Parthenolide (the active compound in feverfew) content varies tremendously from product to product and usually depends on its geographical origin. (The variability in the amount of parthenolide may explain why some studies show relief of pain from migraines or arthritis while others do not.) For this reason, feverfew preparations should be standardized to contain at least 0.2% parthenolide.

Pediatric

Feverfew should not be used in children under 2 years of age.

In older children, adjust the recommended adult dose to account for the child's weight. Most herbal dosages for adults are calculated on the basis of an average of 150 lb (70 kg) adult. Therefore, if the child weighs 50 lb (20 to 25 kg), the appropriate dose of feverfew for this child would be 1/3 of the adult dosage.

Adult

• Prevention of migraine headaches: Standardized feverfew extract (minimum 250 micrograms [mcg] parthenolide) two times daily.
• Treatment of migraine headaches: 1 to 2 grams parthenolide daily.
• Other conditions (such as arthritis): 20 to 60 drops twice a day of 1:1 fluid extract; or 60 to 120 drops twice a day of 1:5 tincture (solution made from herb and alcohol, or herb, alcohol, and water).

The use of herbs is a time-honored approach to strengthening the body and treating disease. Herbs, however, contain active substances that can trigger side effects and that can interact with other herbs, supplements, or medications. For these reasons, herbs should be taken with care, under the supervision of a practitioner knowledgeable in the field of botanical medicine.

Side effects from feverfew can include abdominal pain, indigestion, flatulence, diarrhea, nausea, vomiting, and nervousness. Mouth ulcers, loss of taste, and swelling of the lips, tongue, and mouth may occur in some individuals who chew feverfew leaves. Allergic reactions to feverfew, although rare, have also been reported. In fact, people with allergies to chamomile, ragweed, or yarrow will likely be allergic to feverfew and, therefore, should not take it.

Feverfew may increase your propensity to bleed; therefore, it should be avoided around the time of surgery.

Pregnant and nursing women as well as children under 2 years of age should not take feverfew.

Feverfew can alter the menstrual cycle, so women with a regular menstrual cycle should use with caution.

If you are currently being treated with any of the following medications, you should not use feverfew without first talking to your healthcare provider.

Blood-thinning medications
Feverfew can inhibit the activity of platelets (a substance that plays a role in blood clotting), so individuals taking blood-thinning medications (such as aspirin and warfarin) should consult a healthcare practitioner before taking this herb.

NSAIDs
Although specific interactions between feverfew and conventional medications have not been adequately researched, a potential interaction with non-steroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen, has been identified and may result in decreased effectiveness of these medications. The opposite may be true as well – namely, that NSAIDs can render feverfew ineffective.

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