I goggled it to and it is a homeopathic remedy and a very dangerous one. It is used in a very diluted form and if you're getting it in a commercial tea I would assume it is safe. This is a common theme in homeopathy, to use poisons in trace amounts. This practice is what led to the discrediting of Homeopathy as a legitimate medical practice. The other side of the coin is, it have worked to some degree to have ever had it's own College dedicated to teaching it.It is used externally for bruises and other skin disorders. Arnica has also been shown to help with mouth sores in children with cancer caused by chemotherapy.

I don't know I,ve been drinking it for a couple of months Maybe it's from a different strength or part of the plant I,'ll check it out Its gets rid of the pain that's all I know.The tea is from the flower the root is usually more potent in any herb but if it was,nt o.k. I'm sure Rite Aid would,nt be selling it.I,'ll do some more research on other sites and let you know what I find out.It's my guess Google is referring to the roots.Thanks for posting