Instruct: Classify the given review into positive or negative sentiment.
Query: This book saved my life

I have interstitial cystitis and it's extremely painful.Doctors have been unable to help me. There is only one medication for this condition which would cost me $400 per month. There is no guarantee it would even help. I can't afford to even try it. This book showed me which herbs to take which have been the only thing that has helped me. Without these herbs, I would be miserable. I am so thankful I found this book.