Changes to This Summary (12/23/2013)
Revised text to state that the active substance in milk thistle, silymarin, is a complex mixture of flavonolignans, primarily consisting of the following isomers: silybin (consisting of silybins A and B), isosilybin (consisting of isosilybins A and B), silychristin (also known as silichristin), and silydianin (also known as silidianin).
Revised text to state that the primary active constituent of milk thistle is silymarin, which is composed of the following isomers: silybin (consisting of silybins A and B), isosilybin (consisting of isosilybins A and B), silychristin, and silydianin (cited Napolitano et al. as reference 3).
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