Berberine and barberry (<scp><i>Berberis vulgaris</i></scp>): A clinical review

<jats:p>Barberry (<jats:styled-content style="fixed-case"><jats:italic>Berberis vulgaris</jats:italic></jats:styled-content> L.) has different medicinal applications in folk medicine of Iran. Berberine, an alkaloid constituent of this plant, is present in the roots, rhizomes, stem, and bark of <jats:styled-content style="fixed-case"><jats:italic>B. vulgaris</jats:italic></jats:styled-content> and many other plants. There have been many clinical trials conducted that suggested a wide range of therapeutic applications. Here, we investigated the clinical uses of berberine and <jats:styled-content style="fixed-case"><jats:italic>B. vulgaris</jats:italic></jats:styled-content> in the treatment of different diseases in humans. An extensive search in electronic databases (PubMed, Scopus, Embase, Web of Sciences and Science Direct) was used to identify the clinical trials on <jats:styled-content style="fixed-case"><jats:italic>B. vulgaris</jats:italic></jats:styled-content> and berberine. Lipid‐lowering and insulin‐resistance improving actions are the most studied properties of berberine in numerous randomized clinical trials. There are also clinical trials regarding cardiovascular, anticancer, gastrointestinal, CNS, endocrine, and so on. Berberine has very low toxicity in usual doses and reveals <jats:italic>clinical</jats:italic> benefits <jats:italic>without</jats:italic> major <jats:italic>side effects</jats:italic>. Only mild gastrointestinal reactions may occur in some patients. The purpose of this review is to provide a summary concerning the clinical trials conducted on berberine to improve the clinical application of this nutraceutical in different diseases. In this review article, we used 77 clinical studies on human subjects.</jats:p>