How should potassium be replaced in severe hypokalemia?

In cases of severe hypokalemia, potassium replacement is best achieved through slow intravenous (IV) supplementation. This approach allows for controlled repletion of potassium levels while minimizing the risk of potential complications associated with rapid potassium administration, such as cardiac arrhythmias.

Administering potassium too quickly can lead to dangerous elevations in serum potassium levels, which may overwhelm the body's regulatory mechanisms and cause hyperkalemia. Therefore, administering potassium slowly via IV ensures that the patient can be monitored closely, allowing for adjustments based on serum potassium levels.

While oral potassium is effective for mild to moderate hypokalemia, it is not suitable for severe cases where rapid repletion is required. Subcutaneous injections are not a standard method for potassium replacement due to limited absorption and slower onset of action compared to intravenous methods. Thus, the method of slow IV supplementation is the safest and most effective for managing severe hypokalemia in a controlled environment.