Feverfew
Feverfew has a long history of use in traditional medicine, especially among early European herbalists. Recently, it has become a popular remedy for migraine headaches, menstrual pain, asthma, dermatitis, arthritis, and as an antipyretic. It’s been used as an insect repellant and balm for insect bites, as well as an antidote for overindulgence in opium.
Feverfew has more than 35 chemical components, of which parthenolide, a germacranolide, is the primary constituent. Sesquiterpene lactones are the most well-known and studied constituent of feverfew. Monoterpenes, such as camphor; flavonoids, such as luteolin and apigenin; and volatile oils, including angelate, costic acid, and pinene are also found in feverfew. Traces of melatonin appear in pure leaves and commercial preparations of the herb.
Parthenolide is thought to be the major component responsible for the pharmacologic effects of feverfew. It inhibits prostaglandin synthesis, platelet aggrgation, serotonin release from platelets, release of granules from polymorphonu
clear leukocytes, histamine release from mast cells, and phagocytosis. Parthenolide may have thrombolytic, cytotoxic, and antibacterial activity and may cause contraction and relaxation of vascular smooth muscle.
Monoterpenes, and possibly melatonin, may be responsible for feverfew’s sedative and mild tranquilizing effects. Feverfew is available as capsules, dried leaves, liquid, powder, seeds, and tablets, in products such as Feverfew Extract Complex, Feverfew LF and FL-GBE, Feverfew Power, Migracare Feverfew Extract, Migracin, MigraSpray, MygraFew, Partenelle, and Tanacet.
Reported uses
Feverfew is used most commonly to prevent or treat migraine headaches and to treat rheumatoid arthritis. It’s also used to treat asthma, psoriasis, menstrual cramps, digestion problems, and intestinal parasites; to debride wounds; and to promote menstrual flow. Feverfew is used as a mouthwash after tooth extraction, a tranquilizer, an abortifacient, and an external antiseptic and insecticide.
Administration
- Infusion (steep 2 tsp of feverfew in a cup of water for 15 minutes, or double the amount of feverfew and allow it to steep for 25 minutes): Dosage is 1 cup of the mild infusion three times a day; stronger infusion is for topical use
- Powder: Recommended daily dose is 50 mg to 1.2 g
- Migraines: Dosage is 125 mg of dried leaf preparation every day; T. parthenium content should be standardized to contain at least 0.2% parthenolide, equivalent to 250 mcg of feverfew.
Hazards
Adverse reactions to feverfew include dizziness, tachycardia, mouth ulcerations, GI upset, and contact dermatitis. Feverfew inhibits prostaglandin synthesis and platelet aggregation. Monitor patients taking anticoagulants, antiplatelet drugs including aspirin, and thrombolytics for increased bleeding tendency.
Pregnant women should avoid use because of its potential abortifacient properties. Breast-feeding patients should also avoid use. Patients allergic to members of the daisy, or Asteraceae, family-including yarrow, southernwood, wormwood, chamomile, marigold, goldenrod, coltsfoot, and dandelion, should avoid use. Patients who have had previous reactions to feverfew shouldn’t take it internally. Feverfew shouldn’t be used in children younger than age 2.
Clinical considerations
- Educate patient about the potential risk of abnormal bleeding when combining herb with an anticoagulant, such as warfarin or heparin, or an antiplatelet, such as aspirin or another NSAID.
- If patient is taking an anticoagulant, monitor INR, PTT, and PT. Monitor patient for abnormal bleeding.
- Advise patient to discontinue use immediately if he experiences rash or contact dermatitis because these may indicate sensitivity to feverfew.
- Abruptly stopping the herb may cause “post-feverfew syndrome;’ involving tension headaches, insomnia, joint stiffness and pain, and lethargy.
- If patient is pregnant, planning to become pregnant, or breast-feeding, advise her not to use feverfew.
- Tell patient to remind pharmacist of any herbal or dietary supplement that he’s taking when obtaining a new prescription.
- Advise patient to consult his health care provider before using an herbal preparation because a conventional treatment with proven efficacy may be available.
Research summary
Studies comparing feverfew’s efficacy in Controlling migraines to placebo have generally found a significant clinical benefit from the use of feverfew. Preliminary safety data from clinical trials suggest that the plant is relatively safe, although the incidence of mouth ulcers has been high in some trials. The plant does not appear to be mutagenic, and shouldn’t be used by pregnant women.
Tagged under:antibacterial activity Herbs migraine headaches monoterpenes prostaglandin synthesis rheumatoid arthritis vascular smooth muscle volatile oils Posted by editor on March 9th, 2008 | Filed under Herbs
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