Hi! Yes, I have made that switch! The anastrozole gave me "trigger thumb" at about two months in (my thumbs would get stuck in a bent position, and I had to manually pop them straight; kinda painful, definitely freaky). Stopped anastrozole, the issue resolved, started letrozole, the trigger thumb immediately returned. After an unsuccessful experience with tamoxifen, I started exemestane, and...Hooray! No trigger thumb! I've been taking it for almost a year now with very little side effects. I do feel stiff and creaky in the morning, or after sitting in the car on a long drive, but that gets worked out quickly as I move around. So exemestane is the AI that works for me; maybe it will be great for you, too! If not, try letrozole. There are so many stories of women who can't tolerate one AI, but another works for them. Hugs to all 🙂