Chinese herbs for dementia diseases.

In the last twenty years a considerable body of information has accumulated on the chemical constituents of Chinese herbs and their therapeutic potential. Our evaluation/systematic review [1, 2] of well-designed, randomized double blind controlled trials on Chinese herbal medicines beneficial for the improvement of cognitive function revealed a range of either single herbs or herbal mixtures that provided neuroprotective benefits. Oxidative stress may directly initiate neurodegeneration and herbal antioxidant neuroprotection is considered as a preventative and therapeutic approach. We encountered Acoris gramineus rhizome (AGR), Panax ginseng, Polygala tenuifolia and Poria cocos as the four most frequently used herbs as single/herbal mixtures that were associated with positive cognitive enhancing outcomes. This review focuses on the evidence of their medicinal effects attributed to those constituents present in relatively high concentration.