Hi @anjalima -- I am tolerating Kisqali well. I've been on it for 27 months now and don't intend to stop. It seems to be working. When I first took 600 mg, that was a problem. Be sure they do an EKG after the first week to check for QT prolongation which is a serious cardiac side effect. Only 4% of women get it, but I was one of them. So we had to stop Kisqali for a couple weeks until everything went back to normal and then I started on 400 mg and QT didn't happen again. I started taking Kisqali and Letrozole at the same time. Fatigue, hair thinning, constipation (improved over time), low blood pressure and heart rate. Now joint pain my oncologist thinks is from the letrozole. I also had an issue for a few months with a very itchy rash that lingered if I was in the sun even briefly. My dermatologist thought it was the letrozole. I've never done chemo, but I'm betting Kisqali/Letrozole is way easier to tolerate. 25 months ago, I added Octreotide injections for my neuroendocrine lung cancer so that just piled on and made some side effects worse. Hard to assign blame when you're taking multiple meds. Good luck! It's worth it!