I am diagnosed with CML and new to imatinib—my 4th day today. I started with nilotinib but lasted only for 4 days as I was having chest pain consistently 2hrs after taking the medicine. My doctor asked me stop taking it and switched to imatinib. This time I have a very bad pain in the back and can’t figure out if it’s my spine and I gnash my teeth with the severe pain. I take ibuprofen for pain killer but takes a bit of time before pain subsides. I wonder if it is normal to have so much pain with these medicines.