Yes, my wife has been on Nexavar for kidney cancer for 3 years now. She has had diarrhea as one of the side affects for most of the time. Once the cancer had gone away the doctor lowered her dosage in half which helped them be less severe. Now she only has to go urgently about once every 2-3 days. Things like Imodium and Kaopectate also did help a little, but we have found nothing that really gets rid of the symptoms.
It has hampered our life some (always trying to be near a bathroom), but being in otherwise good health and cancer free is still a good trade off.