Feverfew is a flowering plant in the daisy family that has been used for centuries to prevent migraines. Its scientific name is Tanacetum parthenium, and it grows as a small, bushy herb with white, daisy-like flowers and strongly scented leaves. Native to southeastern Europe, it now grows widely across North America and the rest of Europe, often popping up in gardens, along roadsides, and near old stone walls. The plant’s key active ingredient, parthenolide, is found mostly in the flowers and leaves and is the compound behind most of feverfew’s proposed health effects.
How Feverfew Works in the Body
Feverfew’s main claim to fame is its ability to reduce inflammation and alter how certain chemical signals behave in the brain. Parthenolide, the plant’s signature compound, appears to work through several pathways at once. It helps lower nitric oxide production, a molecule involved in nitrosative stress that plays a role in triggering migraine attacks. Lab studies show it also influences serotonin turnover in brain tissue, which matters because shifts in serotonin levels are closely linked to migraine onset. Some of these effects may come from the plant’s antioxidant properties and its ability to inhibit enzymes that break down serotonin too quickly.
Feverfew also contains other sesquiterpene lactones and flavonoids that contribute anti-inflammatory activity in lab settings, though parthenolide gets the most attention. It makes up roughly 0.1% to over 1% of the dried plant’s weight depending on growing conditions, and supplement quality is often judged by its parthenolide content.
Evidence for Migraine Prevention
Feverfew is most commonly taken as a daily supplement to reduce how often migraines occur, not to stop one that’s already started. A landmark 1988 randomized, double-blind trial found that feverfew reduced both the number and severity of migraine attacks over two-month periods compared to placebo. Vomiting associated with migraines also decreased. Visual analogue scores, a standard way patients rate their own pain, showed significant improvement. Other clinical studies have found that feverfew extracts reduced migraine frequency and pain intensity, and one formulation containing feverfew helped shorten the duration of migraine aura.
The evidence is real but not bulletproof. At least one randomized trial found no difference between feverfew and placebo for migraines, and a systematic review from Memorial Sloan Kettering Cancer Center concluded the overall evidence is “mixed,” noting a need for more high-quality research. In practical terms, feverfew appears to help some migraine sufferers but not all, and it works best as a preventive measure taken consistently over weeks rather than as a quick fix.
Other Proposed Uses
Because parthenolide has anti-inflammatory properties in the lab, researchers have tested feverfew for conditions like rheumatoid arthritis and psoriasis. The results have been disappointing. A clinical trial in rheumatoid arthritis patients found no benefit, despite promising lab data. For skin inflammation, human studies simply haven’t been done yet. A combination of feverfew and ginger has shown some ability to prevent mild headaches from escalating into full migraines, but that’s a narrow use case. For now, migraine prevention remains the only use with meaningful clinical support.
Typical Dosage and Forms
Feverfew supplements come as dried leaf capsules, powdered extracts, tablets, and occasionally tinctures. Health Canada’s monograph recommends 50 to 600 milligrams of dried herb per day for migraine prevention, with no single dose exceeding 200 milligrams. The parthenolide content should be standardized to 0.2% to 2% of the dry weight, with a daily cap of 4 milligrams of parthenolide.
Standardization matters here more than with many herbs. Because parthenolide content varies widely between plants and even between batches from the same supplier, products without a guaranteed parthenolide percentage may contain too little active compound to do anything useful. If you’re choosing a supplement, look for one that lists parthenolide content on the label.
Most people take feverfew daily for at least several weeks before seeing any effect on migraine patterns. It is a preventive strategy, not a painkiller.
Side Effects and Withdrawal
Feverfew is generally well tolerated, but it does have a distinct set of side effects. Stomach upset is the most common complaint. People who chew fresh feverfew leaves, a traditional method of taking it, often develop mouth ulcers and irritation of the lips and tongue. This is one reason capsules and tablets have largely replaced the raw leaf approach.
One unusual risk is “post-feverfew syndrome,” a withdrawal reaction that can occur when people stop taking feverfew after using it for a long time. Symptoms include muscle stiffness, anxiety, moderate pain, rebound headaches, nausea, and vomiting. If you’ve been taking feverfew regularly, tapering off gradually rather than stopping abruptly is a reasonable approach. Some people also develop a red, itchy rash, particularly those with known sensitivities to plants in the daisy family (ragweed, chamomile, marigolds).
Drug Interactions to Know About
Feverfew can interact with several categories of medication. It should be avoided if you take blood thinners like warfarin, antiplatelet drugs, or NSAIDs such as ibuprofen and aspirin, because feverfew may amplify their blood-thinning effects and increase bleeding risk. People already taking prescription migraine medications should also avoid feverfew, as combining it with other antimigraine drugs could cause unpredictable effects. Pregnant women should not take feverfew, as some of its compounds may stimulate uterine contractions.
Regulation and Quality Concerns
In the United States, feverfew is sold as a dietary supplement, not a drug. That distinction matters because dietary supplements are not reviewed or approved by the FDA before they hit store shelves. Manufacturers are responsible for their own safety testing and labeling. The FDA only steps in after a product is already on the market, and only if a public health concern arises. This means quality and potency can vary significantly between brands. Independent third-party testing seals (USP, NSF, or ConsumerLab) on the label offer some reassurance that what’s inside the bottle matches what’s on the label.