Been on Anastrazole and exemestane. Early on, for me at least, side effects were minimal but progressed the longer I was on the medication. Some were with both and one of those was lower back ache and stiffness in the hips to the point where when I stand up, I have to straighten, stretch and balance before I move. Luckily the back pain was not excessive but other pain was why I came off Anastrazole - that knife stabbing pain that moved around and could at times be incapacitating. After about 4 months on exemestane, the extreme fatigue settled in followed by insomnia at about 8 months coupled with weakness - can’t do what I used to do even a year ago. After 16 months, he just now put me on a medication vacation after which I will probably go on letrozole because 3-4 hours sleep isn’t cutting it. Now initially I did have mild osteopenia but declined bone meds (Prolia is nasty stuff and if you come off it wrong, can cause a cascade of spinal fractures) because didn’t feel needed at that level. Increased Ca, D3, K2, strength training and walking and after 2 years, bone scan was normal so currently no bone meds. But I guess those would be my questions - when was last bone scan, on or recently off any bone meds? Ask about checking for spinal lesions (x-ray, CT?) because of these drugs. Exemestane has less of an effect on bones than either Anastrazole or letrozole but as noted, other things are definitely there.