For managing diarrhea with Stage 3B CKD and IgAN:

1. Stay hydrated with clear fluids, but monitor fluid intake carefully
2. Follow BRAT diet (Bananas, Rice, Applesauce, Toast) temporarily
3. Avoid high-potassium/phosphorus foods during episodes
4. Contact your doctor if diarrhea lasts >2 days
5. Don't take over-the-counter anti-diarrheal medications without doctor approval, as some can affect kidney function

Always consult your healthcare provider before making any treatment changes.