Potassium from supplements can cause diarrhea, nausea, stomach pain, mild gas and vomiting, although these
side effects may be reduced when
potassium is taken with meals. More serious
side effects, although less common, include confusion, irregular heartbeat, numbness or tingling in hands, feet, or lips, shortness of breath, anxiety, tiredness or weakness. They can also cause more severe stomach pain, chest or throat pain (when swallowing).