It has been 6 months for me. I take my 1mg Anastrozole at breakfast. I usually need a long afternoon nap. I usually wake up with numb, tingling left hand, but clenching, opening and closing helps. No pain. At 64, morning stiffness is there, but goes away once up and moving. I had an odd 3 weeks after my first 2 months- forgetful, loss of train of thought, inability to retrieve words and the wrong words coming out in my speech..like early dementia. That disappeared after 3 weeks. My doctor said he'd never heard of this side effect. Perhaps I should have described it as "brain fog" as others have. Make sure to keep up Calcium and vit D, do weight bearing exercise(walking is fine) to keep up bone strength. Also, I take Alendronate sodium once a week for previously diagnosed osteopenia. I did just get an Rx for a low dose estrogen for vaginal dryness, since that has been painful for any intimacy. Hope it helps. So, it's been less than a year for me, but I am tolerating Anastrozole well.