Side Effects and Cautions

• In clinical trials, milk thistle generally has few side effects. Occasionally, people report a laxative effect, upset stomach, diarrhea, and bloating.
• Milk thistle can produce allergic reactions, which tend to be more common among people who are allergic to plants in the same family (for example, ragweed, chrysanthemum, marigold, and daisy).
• It is important to inform your health care providers about any herb or dietary supplement, you are using, including milk thistle. This helps to ensure safe and coordinated care.