Milk thistle derives its medicinal benefits from its active ingredient, silymarin. Milk thistle does not interact with any of the direct-acting antivirals commonly used to treat hepatitis C.
Although milk thistle doesn’t interact with medicines used to treat hep C, you may want to stop taking it because independent lab analysis by ConsumerLab.com found that nearly all the milk thistle sold in the United States falls below clinical standards. In other words, there wasn’t much of the active ingredient silymarin in the product. Also, despite the claims, milk thistle may not do much to help the liver.
If you want to help your liver, it’s best to stick to a healthy diet and lifestyle. Be sure to get regular medical care. These will help your liver more than any supplement can.