so assume you mean Dasatinib?
I switched from Imatinib about 3 years ago, following a mutation of some sort
It has really transformed my life in many ways, On imatanib the side effects where tolerable but not great. However have switched:
1. I lost the 10kgs I had put on in 3 months - without changing diet
2. 99% of the nausea and occasional diarrhoea disappeared over night
3. I became able to do physical exercise for more than 20 minutes at a time - regular 10K runner now
4. My energy levels increased massively
5. My skin and toe/finger nails returned to normal - prior to that they where very thin. I couldn't stay in sun for more than 15 minutes without burning, nails split easy
6. Easy bruising gone
7. Cuts that wouldn't heal gone
8. Excema reduced (always struggled with that prior to dx)
I was on Imatanib for 4 years I think prior to the switch and a 43 year old male...
Of course everyone is different and I guess you won't know until you try - but hopefully my experience will make you less worried...
Also if you are in England/wales I didn't think you could get Dasatanib for new patients any more unless you applied for something special
Rob