Author: Dylan Luyten, MD
- Most important questions to answer with low potassium are 1. What are their symptoms? 2. Can they take potassium by mouth?
- Oral repletion is faster, cheaper, and more effective than IV repletion.
- Give IV potassium when patients have K < 2.5 mmol/L or present with arrhythmias and/or characteristic EKG changes (flattened T waves).
- Most patients who are hypokalemic are hypomagnesemic and require magnesium supplementation. Checking a level is unnecessary.
Ashurst J, Sergent SR, Wagner BJ, Kim J. Evidence-based management of potassium disorders in the emergency department. Emerg Med Pract. 2016 Nov 22;18(Suppl Points & Pearls):S1-S2
Whang R, Flink EB, Dyckner T, et al. Magnesium depletion as a cause of refractory potassium repletion. Arch Intern Med 1985; 145:1686.