High blood pressure, or hypertension, is a common disorder that can raise your risk of heart disease and stroke. Your pressure reading includes an upper number, the systolic pressure caused by your heart beating, and a lower number, the diastolic pressure exerted when your heart is resting. Medline Plus warns that a reading of 140 over 90 or higher may indicate hypertension. Medication can help eliminate excess fluids, and relax and widen blood vessels, but might can have unpleasant side effects. Certain herbs may be effective in preventing and treating high blood pressure.
Hawthorn (Crataegus spp.) is a diuretic herb that helps reduce blood pressure. The plant contains natural antioxidants called flavonoids that have a positive effect on your heart. In his 2003 book, Medical Herbalism: the Science and Practice of Herbal Medicine, herbalist David Hoffmann recommends using an extract of the whole plant, since the individual plant chemicals do not work in isolation. Hoffmann states that hawthorn increases contractions of the heart muscle and dilates coronary arteries. A study published in 2010 issue in "Phytomedicine" found that an extract of hawthorn enhanced contractions in hearts damaged by insufficient blood supply, and helped heal tissue damage to the heart muscles. Hawthorn may cause nausea in some people and you should consult a doctor before combining it with other medications.
Linden (Tilia platyphyllos, T. cordata is a deciduous tree whose flowers and bark are part of traditional medicine in Europe and Asia because it acts as a hypotensive and relaxing herb. David Hoffmann states that linden is typically used for high blood pressure associated with arteriosclerosis and nervous tension. In his 2001 book, The One Earth Herbal Sourcebook, herbalist Alan Tillotson states that linden lowers blood pressure and that a linden-rauwolfia tincture combined with a lower dose of prescription blood pressure medicine often works in cases of moderate hypertension. Although considered a safe herb, linden may cause allergic skin rashes in some people.
Mistletoe (Viscum album) is a strong hypotensive and nervine herb. Traditionally, it is used to treat cancer because it has immune stimulating properties, but mistletoe also has an effect on blood viscosity, or the thickness of your blood. If your blood is too thick, its flow through blood vessels can be reduced, putting more pressure on the arteries and raising your blood pressure. A study published in 2009 "Journal of Ethnopharmacology" found that an extract of mistletoe prevented changes in blood viscosity. You should avoid mistletoe if you are pregnant or breast-feeding, and should see your doctor if you experience an allergic reaction after consuming it.
The yarrows consist of about 85 species in the genus Achillea. Achillea wilhelmsii and Achillea millefolium are two popular yarrows with hypotensive properties. Herbalist David Hoffmann states that Achillea millefolium lowers blood pressure by dilating the peripheral blood vessels. A study published in the 2000 issue of Drugs Under Experimental and Clinical Research found that Achillea wilhelmsii was effective in lowering the diastolic and systolic blood pressure in hypertensive subjects. The researchers attribute the hypotensive action to the flavonoids and lactones in the plant. Don't take yarrow if you're pregnant or breast-feeding, or if you are allergic to members of the aster family.