Danshen, the active ingredient in some traditional Chinese medicines used to promote blood flow shows some promise for treating hypertension:

“Many patients with high blood pressure have sought relief from complementary and alternative medicine (CAM). In so doing, many have consumed danshen, a Chinese herb used in Oriental medicine that promotes blood flow and treats cardiovascular disease.

Tanshinone IIA is an active ingredient of danshen. Since tanshinone IIA is widely available, a team of researchers has used it to investigate if this active ingredient can reduce blood pressure. In a soon-to-be-released study, using an animal model, the scientists have found that tanshinone IIA does reduce blood pressure. “