Hi Onekayaker -
I'm surprised you were prescribed 100 mg Sprycel at M.D. Anderson. They were pioneers showing 50 mg should be the starting dose. You go up or down from there. I can appreciate that you need to follow your doctor's advice, but my doctor, also at M.D. Anderson, (I am also in Houston) who is a specialist in CML never started me at 100 mg. I take only 20 mg and I am PCRU (undetected). He said Sprycel is very potent and has major impact on the body other than CML. Talk to your doctor about lowering your dose so you can get over the side effects adjustment. You can always increase dose later if necessary. You have plenty of time given where your CML is currently (caught early). Keep in mind that more drug does mean more response. It doesn't work that way. It's a balance between your body naturally fighting CML along with Sprycel. Too much Sprycel and it actually inhibits your body's natural ability to fight the disease (suppression of T-cells). So each patient has to find their sweet spot. Most will do very well at 50 mg and have a worse response going up to 100 mg!
Since you are just starting - it is very important you test your blood counts weekly until your response is stable. One huge side effect of 100 mg Sprycel is myelosuppression. This is when your white blood cell count, platelets or other cell counts drop significantly below normal. Neutrophils, in particular, is the concern mostly. My Neutrophils dropped to dangerous levels in less than a week. I had to stop Sprycel during this time to allow for recovery. My doctor told me that I am very "sensitive" to Sprycel and that could be a good thing. Research shows patients who have a severe reaction to Sprycel in the form of myelosuppression can also have a very deep response to the drug on a very low dose.
I have no side effects that I can feel.
Your goal is to find the right dose that works for you. Lower is better IF lower works. It's that simple.
Track your blood counts - watch your Neutrophils, in particular, and if they fall too low - stop Sprycel, recover and then re-start on a much lower dose.
I was lowered to 20 mg and have never gone up since. I'm looking forward to stopping altogether after my next PCR test to see if I can stay "undetected" without Sprycel.