Hi ipg. Welcome to the forum.
I can suggest two alternative ways of improving on the diarrhoea front.
1. I gradually umproved my diet, to boost my health and prognoais. Moved towards emphasising whole foods: beans, nuts, cereals/bread, fruit and veg, some (but not a lot of) dairy and eggs. Very little junk, lots of fibre.
That improved my diarrhoea. If you are wondering why I am not mentioning meat, that’s because I have been vegetarian for decades.
2. The effects of lenalidomide can accumulate over time. About 18 months into remission, diarrhoea returned and fatigue got worse. In response, my doctor cut the dose from 5mg to 2.5mg. That dealt with it again.
Regards
Rabbit