Here is my story. I started on letrozole (sp?) and got horribly anxious and depressed along with developing terrible backaches. I switched to anastrozole and was afraid it would cause the same emotional problems that I had developed before while on the other aromatase inhibitor. So I was prescribed Lexapro to help me calm down while I was taking Anastrozole. Thankfully, I was able to tolerate Anastrozole physically and I remain on Lexapro so I don't become so horribly depressed. Good luck.