Any other ways of stopping my moms runs from leukemia treatment, loperamide doesn't work?

Cause of diarrhea. There are many reasons why your mother could be having diarrhea. The best treatment will depend on the cause. This could be related to chemotherapy, infection, etc. Once her physician determines the cause then a treatment can be identified.
Speak with doctor. Any symptoms associated with treatment, if not under control, should be discussed with your doctor. Tests may be required to determine why diarrhea is occurring.