II. Indications
III. Precautions
- Magnesium Replacement is often needed in conjunction with Potassium
- Adjust protocol for renal disease
- Oliguria: Urine Output < 30 ml/hour
- Renal Failure: Serum Creatinine > 3.0 mg/dl
IV. Background
- Expect 0.1 mEq increase in Serum Potassium for every 10 mEq Potassium administered
V. Preparations
-
Potassium Chloride
- Potassium Chloride IV (see below)
- Extended Release Potassium Chloride Tablets (preferred)
- Order generic Potassium chloride ER ($15 per month)
- Available as 8, 10, 15, 20 meq tablets
- K-DUR brand-name is not available in U.S. as of 2016
- Immediate-Release Potassium Chloride Powder
- Expensive ($290 per month)
- Diluted in liquid and are less than palatable
- Better tolerated in divided dosing (20 mEq at a time)
- Indicated in patients with Feeding Tubes and those with Delayed Gastric Emptying
-
Potassium bicarbonate (or oral preparations with citrate or gluconate, or IV Potassium acetate)
- Consider in Metabolic Acidosis with Hypokalemia
- Potassium Bicarbonate Effervescent Tablet 25 mEq orally at 1-2 tabs (25 to 50 mEq) per dose
- Potassium bicarbonate is more palatable than Potassium chloride
-
Potassium phosphate (IV)
- Most Dietary Potassium is in the form of Potassium phosphate
- Indications: Hypokalemia with Hypophosphatemia
- References
- (2016) Presc Lett 23(4): 23
VI. Management: Oral Potassium Replacement
- Dietary Sources: Fruits and Vegetables
- See Foods with High Potassium Content
- May supply 40-60 meq/day
- However 40 meq is equivalent to 4 bananas which may be difficult to sustain
- Dietary Potassium (Potassium phosphate) is less effective replacement than KCl
- Most Hypokalemia is associated with concurrent chloride depletion
- Oral KCl 20-40 meq immediate release powder in water or juice or KCl extended release tablets
- Powder has unpleasant taste (patients may prefer Swallowing tablets)
- Serum Potassium < 3.0 mEq/L (total body deficit 200-300 meq)
- Give KCl 20 meq orally every 2 hours for 4 doses, then recheck level OR
- Give KCl 40 meq orally every 2 hours for 2 doses, then recheck level
- Typically continue Potassium Replacement at 20 meq twice daily for 4-5 days
- Serum Potassium: 3.0 to 3.5 mEq/L (total body deficit 100-200 meq)
- Give KCl 20 mEq orally every 2 hours for 2 doses OR KCl 40 mEq once, then recheck level
- Typically continue Potassium Replacement at 20 meq twice daily for 2-3 days
- Maintenance dosing
- KCl 20 mEq orally daily when on Loop Diuretics or for Hyperaldosteronism
VII. Management: IV Potassium Replacement
- IV Preparations
- Potassium Chloride (KCl) 10 meq IV "K bump"
- Potassium Chloride (KCl) 20 meq use is limited to delivery via Central IV Access
- IV Replacement Algorithm
- Use 10 meq KCl IV in 50ml solution over 30 minutes minimum
- Dextrose containing IV solution not recommended
- Risk of Insulin induced exacerbation of Hypokalemia
- In select situations, may give up to 40 meq in 1 hr
- Example indication for faster delivery: DKA
- Cardiac monitoring if replacing >10 mEq per hour
- Recheck Serum Potassium after 30 mEq given
- Dextrose containing IV solution not recommended
- Serum Potassium < 3.0 mEq/L (total body deficit 200-300 meq)
- Give KCl 10 meq IV slowly every hour for 5 doses, then recheck level
- Serum Potassium: 3.0 to 3.5 mEq/L (total body deficit 100-200 meq)
- Give KCl 10 meq IV slowly every hour for 3 doses, then recheck level
- Use 10 meq KCl IV in 50ml solution over 30 minutes minimum
VIII. References
- Hayes and Swaminathan in Herbert (2021) EM:Rap 21(5): 7-9
- Kim (2023) Am Fam Physician 107(1): 59-70 [PubMed]
- Viera (2015) Am Fam Physician 92(6): 487-95 [PubMed]