Mild gastrointestinal distress is the most common adverse event reported for milk thistle. It is also found in the silymarin extract from the milk thistle seeds. A laxative effect for milk thistle has also been reported infrequently. Milk thistle has also been known to be used as food. Certain complementary medications, e.g., milk thistle and silymarin, appear to offer some benefit. Milk thistle may appear to stimulate prolactin due to possibly estrogenic activity.