Question about taking too much supplemental potassium: Does it cause diarrhea? I've been needing about 2500-3000 mg of supplemental potassium a day. In the last week or so, some of the low potassium symptoms have eased off occassionally. This morning I took potassium chloride as usual but had the impression pretty quickly that I didn't need it. Within 4 hours my digestive tract cleaned itself out. Cause and effect?