Properties and Uses:Prevents attacks of migraines. In one study of 300 users of feverfew, 72% reported that their headaches were less frequent or painful. Feverfew is also shown to be helpful in alleviating inflammation and discomfort of arthritis. CAUTION: In about 15% of users, a slight side effect is the formation of small sores in the mouth. Increased Vitamin C can eliminate the sores.