I cannot stop taking premarin despite the research of complications. Am I a victim of malpractice?

I was started on premarin at the age of 46 as a precursor to menopause because the physician determined it would be a good tool to prevent heart disease which is prevalent in my family. (Both parents died of heart failure in their 50's). I am now 63, and unable to stop taking the premarin without having extreme hot flashes, night sweats, day sweats, and overall embarrsing clothes drenching sweat episodes. I have tried all other menopause over the counter drugs to no avail. I was not informed of the permanent negative effects of the premarin except what was in the reseach about possible breast cancer. I was also told that the benefits would outweigh the negative. Do I have legal recourse? I was told I must be on premarin the rest of my life despite the negative effects. Is this malpractice?