Hypokalemia is a common biochemical abnormality. Severe hypokalemia can produce cardiac rhythm alterations and neurologic manifestations. Early detection and treatment allow clinician to prevent morbidity and mortality from cardiac arrhythmias and respiratory failure. Here, we describe a case of severe hypokalemia inducing pseudoischemic electrocardiographic (ECG) alterations and quadriplegia, in a patient affected by chronic diarrhea. Electrocardiographic alterations and neurologic manifestations completely disappeared after potassium replacement; however, prolonged potassium supplementation was required to achieve the normalization of plasmatic potassium levels. Consecutive figures show ECG improvement until normalization of ECG findings.