Like a lot of people on here, I was changed from Eltroxin to Mercury Pharma generic levothyroxine about 6 months ago. I thought I was tolerating the change quite well but have recently noticed that my heart rate has dropped from 80+ to low 70s and my hair is a lot thinner. I've always had thick hair so the difference is noticeable. I am 49 so my doctor will probably say it's the menopause but I'm wondering if it is the change to generic thyroxine. Any advice would be appreciated please.