HIGH BLOOD PRESSURE LOWERING HERBS AND SUPPLEMENTS
Green Coffee Bean Extracts Chlorogenic acids (CGA) in green coffee bean extract (GCE) reduce blood pressure in spontaneously hypertensive rats and humans. Researchers found no apparent side effects of green coffee bean extract in dosing 28 subjects suffered from mild hypertension with 140 mg/day of the extract.  However, long-term studies are needed to ensure the safety.
Garlic Extracts In a of spontaneously hypertensive rats, researchers found both aged garlic extract and raw garlic extract reduced the increased systolic blood pressure. However, researchers also found that decreased amounts of erythrocytes and increased amounts of reticulocytes in the animals taking the raw garlic.  Thus, the users should watch out the possible side effects of garlic supplements.
Ginkgo Biloba Extracts Ginkgo biloba extract (Ginkgo) produced vasodilation via the nitric oxide pathway in aortic segments isolated from Wistar rats. Administration of ginkgo biloba extracts did not change systolic blood pressure in Wistar Kyoto rats, but significantly decreased systolic blood pressure in spontaneously hypertensive rats. Together with a few basic studies, researchers concluded that ginkgo biloba extracts enhanced endothelium-dependent vasodilation and elevation of the endothelial intracellular Ca(2+) level in spontaneously hypertensive rats, resulting in hypotension. 
In a study, researchers administered an extract of ginkgo biloba to stroke-prone spontaneously hypertensive rats at 60 and 120 mg/kg each day for three weeks. They observed a suppression of the age-related increase in blood pressure. 
Yeast Extracts Researchers isolated a peptide fraction KRF814 from the hydrolysate of brewer's yeast and this KRF814 showed an inhibitory effect on angiotensin-converting enzyme (ACE) in vitro. The researchers fed male spontaneous hypertensive rats with brewer's yeast BY-G and KRF814; they found the systolic blood pressure was significantly decreased in the rats. The active ingredients of KRF814, was about 60% of the potency of captopril. 
Tomato Extracts Tomato extract contains carotenoids such as lycopene, beta carotene, and vitamin E, which are known as effective antioxidants. Researchers found that a short-term treatment with antioxidant-rich tomato extract can reduce blood pressure in patients with grade-1 hypertension, naive to drug therapy. 
Bulbus Fritillaria Water Extracts In a study of rats treated with NG-nitro-L-arginine methylester (high blood pressure inducer), Bulbus Fritillaria water extract restored systolic blood pressure to normal level in rats. 
Vernonia Polyanthes Less. Extract A rat study showed that oral crude Vernonia hydroalcoholic extract decreased arterial blood pressure dose-dependently. During the study, researchers observed a significant rise in creatinine clearance and a fall in fractional post-proximal sodium excretion. 
Green Tea Extract In a study of isolated aortic strips of the normotensive rats, green tea extract greatly inhibited the phenylephrine induced contractile responses in a dose-dependent fashion. Green tea extract at high concentrations could be able to also depress the high potassium-induced contractile responses. On the other hand, the key ingredient of green tea (epigallocatechin gallate, EGCG, 12 microg/mL) failed to affect the corresponding contractile responses. 
C. Sativus Petals Extracts In a study of anaesthetized rats, extracts of C. sativus petals reduced the blood pressure in a dose-dependent manner. Administration of 50 mg/100 g of aqueous extract changed the blood pressure from 133.5+/-3.9 to 117+/-2.1 (mmHg) in the study. 
Olive Leaf Extract A specially prepared olive leaf extract (EFLA 943) has been shown for its blood pressure lowering activity in rats rendered hypertensive by daily oral doses of L-NAME (NG-nitro-L-arginine methyl ester, 50 mg/kg) for at least 4 weeks. The findings confirm previous reports on the hypotensive effects of olive leaf. 
Commiphora Opobalsamum Extract The intravenous administration of 4 mg/kg of the aqueous extract depressed systemic arterial blood pressure of anaesthetized rats by 20% and reduced heart rate by 14%. Pretreatment of atropine sulfate inhibited the hypotensive effect of C. opobalsamum, suggesting its action was via the activation of muscarinic cholinergic receptors. 
Clerodendron trichotomum Thunb Clerodendron trichotomum Thunb. is a herb which has been used for treatment of hypertension in Chinese medicine. Acute oral administration of the extract reduced blood pressure of spontaneously hypertensive rats but not of normotensive control rats. 
Researchers have demonstrated the benefits of dietary flavonoids derived from the ethanolic extract of licorice root against atherosclerotic lesion development in association with inhibition of low-density lipoprotein (LDL) oxidation in atherosclerotic mice. Furthermore, they found licorice extract supplementation also reduced systolic blood pressure by 10%. 
Neem Leaf Extract Intravenous administration of Neem leaf alcoholic extract resulted in initial bradycardia and then cardiac arrhythmia in rats. The side effect is too serious, do not take this extract without doctor's recommendation. 
Root of Bredemeyera floribunda Willd The infusion of the dried roots of Bredemeyera floribunda Willd. is used in Brazilian popular medicine as a potent diuretic for hypertension and nephrolithiasis (renal calculi). Intravenous administration of crude root-extract (20-80 mg/kg) to anesthetized rats induces clear dose-dependent and reversible hypotensive responses. However, it can lead to bradycardia and death at high doses. Discuss with your doctor about its toxic side effects before taking this herb. 
Extract of Hibiscus Sabdariffa Hibiscus sabdariffa caused a dose-dependent decrease in mean arterial pressure of the rats. 
Curcuma Herbs (Turmeric Curcumin) Curcuma herbs have shown of blood pressure lowering effects and protective effect on the endothelium in spontaneously hypertensive rats. The effects of C. longa, which induces only endothelium-independent vasodilatation, while C. zedoaria, which induces both endothelium-dependent and -independent vasodilatation in spontaneously hypertensive rats. The mechanisms probably involve a radical scavenging effect and improvement of hemorheology. 
Yishenjiangyafang Yishenjiangyafang is a prescription of Chinese traditional herbs used for renal hypertension. It reduced blood pressure in a rat study. 
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