Berberine is the orange-yellow alkaloid found in the bark and roots of 4 distinct plants. The four plkants are: Oregon Grape (Mahonia aquifolium), Goldenseal (Hydrastis canadensis), Barberry (Berebris vulgaris), and Chinese goldenthread (Coptis chinensis).
I use berberine for many gastrointestinal ailments. I especially use these herbs as an antimicrobial for most infections. It is a bitter herb with many uses.
One must remember that this herb inhibits the cytochrome 450 system. This is especially important as it can interact with common used medications that work on the P450 system. Such medications may include beta blockers, ARB hypertensive (such as losartan), and even some antibiotics. It does interact with statins.
There are important studies available for the use of berberine in cardiovascular disease especially blood pressure and hyperlipidemia. It also can inhibit clot formation.