I have been on Letrezole for 2 months after total mastectomy of one breast, 6 months of chemo and 3 weeks of daily radiation. The Leterzole has caused pain in my joints, lower back pain, sometimes extreme during the night but fine during the day when I’m moving and two trigger thumbs, one I have had a cortisone injection for.
I will persevere for 6 months to see if it settles down but it’s not pleasant.
I wish you all the best.