How much?
I had surgery over a year ago and my hair fell out too. I tried the Biotin but, honestly, I read so many posts that said the Biotin wouldn't help...also read one that said if you didn't take it BEFORE the surgery then it wouldn't help! That one made me mad enough to ask my surgeon because I was livid they hadn't told me to take it pre-op....he told me the hair is going to fall out for a few months. Period. He said keep eating your protein first and make sure you're getting all your protein and taking your vitamins. It will stop in 3-4 months. Now it wasn't what I wanted to hear so, I kept taking the Biotin anyway....sorry I don't remember the dosage....but, he was right and my hair quit falling out after 3 months. I personally believe it's just part of the process and there's not much you can do but, hang on until it's over. If your hair is already thick, then I wouldn't worry too much! My hair was already thin and I felt like I was going bald! I simply cut my hair into a short and sassy style and went on with life! My hair is thicker and still short at this point...I love my new style!
Best of luck to you!