I have been taking the herb Butterbur for several weeks now for my itchy eyes and throat. I have been trying to figure what is causing the allergy so I can try and get to the root of the problem but haven't as of yet. The Butterbur works great as long as I'm consistent. But when I back off the itching comes back with a vengeance. The thing I've read about Butterbur is it can cause liver problems if taken longer than 12 weeks. This concerns me because I'm closing in on about 8 weeks and am no closer to finding a cure. Just the Butterbur bandaid. Does anyone know anything about this herb and possibly give me any advise concerning the long term side effects about it? It's the only thing that's helping me and the thought of having to stop taking it is putting me in panic mode.