Sodium bicarbonate also is used to help drive the potassium intracellularly, but it is only effective if the patient is acidotic (because of electrolyte exchange at the sodium/potassium ATPase pump). 2. 6 this is another agent that is not needed in every patient. Sodium bicarbonate begins working in 30 to 60 minutes and continues lowering the serum potassium for several hours. 2 The typical dose for treatment of hyperkalemia is 50 mEq of sodium bicarbonate (one 50-mL unit of 8. 4% sodium bicarbonate) infused intravenously over 10 to 20 minutes diluted in at least 50 mL D5W, or by intravenous push if the ECG indicates imminent or current. Cardiac arrest. Keep in mind that in the absence of acidosis, sodium bicarbonate will not help lower the serum potassium and may be. harmful to the patient