Meadowsweet - Filipendula ulmaria
According to the Bulletin of Experimental Biology and Medicine, a 2006 Russian study on experimental toxic hepatitis reported that meadowsweet prevented damage to the liver and had an antioxidant effect.
Meadowsweet has natural salicylates, is an analgesic, antirheumatic, gentle astringent, and antacid. It is used to treat colds, bronchitis, headache, fever, upset stomach, cyctits, gout, rheumatism, arthritis, diarrhea, excessive menstrual bleeding, and heartburn.
References:
http://www.ncbi.nlm.nih.gov/pubmed/17369943
http://www.altmd.com/Articles/Meadowsweet-Herbal-Remedies