Diarrhea requires attention with IGAN since it can affect your hydration and medication absorption. Stay hydrated with clear fluids and electrolytes. If diarrhea persists more than 2-3 days or you're taking immunosuppressants, contact your doctor - they may need to adjust medications or check for infection. Monitor your urine output and any changes in foamy urine or blood in urine while having diarrhea.