My experience with Abemaciclib is similar to @Katie. Started at 150 and was tolerating for a few weeks then had extreme diahorrea and unknown to me was anemic (not related to iron but the medication) I thought I was just unfit after the year of treatment. Ended up with a blood transfusion and bags of potassium. Oncologist dose reduced to 100 mg which has helped. I do find if I start new medication, recently on Veoza for menopause symptoms, I had half a day of an upset stomach. This has settled now. I recently had ovaries and fallopian tubes removed with immediate paws symptoms, while it has been a week on Veoza, no more zoladex. I am also on letrozole.