I noticed hair loss around month 3 and started biotin 2500mcg/day. Think it slowed the progression of the loss. Coincidentally, yesterday had a conversation about hair loss with a friend of mine who had cancer and lost all of her hair and is still taking chemo on a maintenance basis (for the next year at least).
She mentioned it seemed that more of her hair was coming in quicker. Seems that not all hair strands start growing at once. Her doctor told her to use a special shampoo, Nioxin. She thinks its working. Here's some info I found on it. I have no idea how valid this is, but in my eyes, its worth a try:
http://womenshair.about.com/od/probl.../fr/nioxin.htm