Dong quai, garlic, ginger, Ginkgo biloba, bilberry and feverfew can increase bleeding time. Tanacetum parthenium, known as feverfew, is a flowering plant in the daisy family, Asteraceae. For combating acne and rosacea, green tea, niacinamide and feverfew are considered efficacious. Other familiar species include costmary ("T. balsamita") and feverfew ("T. parthenium"). In traditional herbal medicine, feverfew has been used for fever, headache, arthritis, and digestive problems. Many herbal supplements have blood-thinning properties, such as danshen and feverfew. Feverfew may cause allergic reactions, including contact dermatitis. The feverfew plant is used in herbalism for a variety of ailments. Common names include Santa-Maria, Santa Maria feverfew, whitetop weed, and famine weed. The active ingredients in feverfew include parthenolide. Members of the genus are commonly known as feverfew. Feverfew should not be taken by pregnant women. Arthur fails his first try, then dodges Feverfew and severs his head. Fenella Feverfew is an unseen character in the book series. There are no published "in vivo" studies of parthenolide or feverfew for humans with cancer.