Hypokalemia medical therapy

; Associate Editor-In-Chief: ; Assistant Editor(s)-In-Chief: Jack Khouri

Overview
The most important step in severe hypokalemia is removing the cause, such as treating diarrhea or stopping offending medication.


 * Patients treated with loop or thiazide diuretics can be offered medications that counteract their kaliuretic effect such as aldosterone antagonists (spironolactone and eplerenone) or distal sodium channel blockers (eg, amiloride).
 * The combination of thiazide and loop diuretics should be avoided.
 * Oral potassium administration is safer than the IV route.
 * An oral dose should not exceed 20-40 mEq.
 * IV potassium infusion should be reserved for symptomatic patients with severe hyperkalemia and patients who can't take oral supplements.

Mild hypokalemia

 * Potassium levels in the range 3.0-3.5 mEq/L.
 * Represent potassium deficit of 200-400 mEq.
 * May be treated with oral potassium salt supplements: potassium chloride KCl (Sando-K®, Slow-K®) or potassium bicarbonate KHCO3 (which can be generated from the metabolism of many organic salts eg, potassium citrate, potassium gluconate, etc).
 * Potassium-containing foods may be recommended, such as tomatoes, oranges or bananas, but they are less effective than oral supplements.
 * Both dietary and pharmaceutical supplements are used for people taking diuretic medications (see Causes, above).
 * KCl is the most effective replacement for metabolic alkalosis-associated hypokalemia.
 * KHCO3 and the organic "alkalinizing" salts potassium citrate and potassium gluconate are recommended for hypokalemia associated with metabolic acidosis (chronic diarrhea, renal tubular acidosis,etc).

Severe hypokalemia

 * Potassium levels below 3.0 mEq/L
 * Potassium levels between 2.0 and 3.0 correspond to 400-800 mEq deficit.
 * It may require intravenous supplementation. Typically, saline is used, with 20-40 mEq KCl per liter over 3-4 hours (ie, at an infusion rate of 10 mEq/L/h)
 * Giving IV potassium at faster rates may predispose to ventricular tachycardias and requires intensive ECG monitoring.
 * Giving IV KCl at doses >60 mEq/L are painful and can cause venous necrosis.
 * Difficult or resistant cases of hypokalemia may be amenable to amiloride, a potassium-sparing diuretic, or spironolactone.
 * When replacing potassium intravenously, infusion via central line is encouraged to avoid the frequent occurrence of a burning sensation at the site of a peripheral IV and the aforementioned venous necrosis. When peripheral infusions are necessary, the burning can be reduced by diluting the potassium in larger amounts of IV fluid, or mixing 3 ml of 1% lidocaine to each 10 meq of KCl per 50 ml of IV fluid. The practice of adding lidocaine, however, raises the likelihood of serious medical errors.
 * Potassium infusions via a central line can reach 200 mEq/L (20 mEq in 100 mL of isotonic saline (see below)) but the administration rate should not be greater than 10–20 mEq per hour.
 * Saline solutions are preferred to prevent potassium transcellular shifting that is triggered by dextrose-induced insulin release!