Blessed thistle safe for kdney stones?

Probably: Most herbal supplements are safe, but should always be cleared with your physician especially if you are taking other medicines, or have medical conditions which may be affected by the herbs.

Neutral: Blessed thistle isn't known to impact kidneys w/ only short term use. However: it does contain tannins. Chronic tannin use can be associated with stones. Blessed thistle interacts w/ some medications--elevating levels of some in your bloodstream & decreasing others. If on these medications, taking it may then have an unexpected impact on kidneys. That aside, this herb is felt to be safe overall.