Comparison of Potassium Salts

Full update February 2021

U.S. products are prescription unless otherwise indicated. In Canada, oral potassium salts do not require a prescription; however, those with more than 5 mEq (mmol) per single dose are only available from the pharmacist and must be kept behind the counter.1 To reduce esophagitis with oral potassium, counsel patients to drink at least 200 to 250 mL of water and stay upright for at least 30 minutes after administration.2 Divide larger daily oral doses (such as >20 mEq [mmol]) to reduce the risk of GI problems.3 Also see our chart, Potassium Content of Foods and Salt Substitutes.

*1 mEq of potassium = 1 mmol of potassium*

Potassium Salt/ Formulations

Example Brands/
Strengths

Comments

POTASSIUM CHLORIDE: 750 mg of potassium chloride is equivalent to 10 mEq (mmol) of potassium.

Wax-matrix tablet,
slow-release

Generics: 8 mEq, 10 mEq (U.S.), 20 mEq (U.S.)
K-Tab (U.S.): 8 mEq, 10 mEq, 20 mEq
Klor-Con (U.S.): 8 mEq, 10 mEq

 

The potassium salt of choice for most as chloride loss commonly occurs with potassium loss from diuretics or vomiting.3

Potassium chloride has better GI absorption compared to other potassium salts.4

Wax-matrix tablets may cause more GI irritation compared to microencapsulated formulations.3,5

Oral liquid formulations act quickly and have the least potential of causing GI irritation. However, they must be diluted and have poor adherence due to a strong unpleasant taste.3,5

Microencapsulated tabs can be dispersed in 120 mL water, let sit two minutes, stir 30 seconds, then drink. Rinse cup with 30 mL of water and drink, then repeat with 30 mL more.4

Microencapsulated capsules can be opened and sprinkled onto a small amount of food.4

Some wax-matrix formulations produce a “ghost” tab in the stool.4

Injectable solution is considered a high-alert medication by ISMP.6

 

Microencapsulated tablet, sustained-release

Generics: 10 mEq (U.S.), 20 mEq
Klor-Con M10 (U.S.): 10 mEq
Klor-Con M15 (U.S.): 15 mEq
Klor-Con M20 (U.S.): 20 mEq

 

Microencapsulated capsule, sustained-release

Generics: 8 mEq, 10 mEq (U.S.)
Klor-Con Sprinkle (U.S.): 8 mEq, 10 mEq

Powder packets for oral solution


Generics (U.S.): 20 mEq
Klor-Con (U.S.): 20 mEq

 

Oral liquid

Generics: 20 mEq/15 mL (10%),
40 mEq/15 mL (20%) (U.S.)

 

Injectable solution

Generics (must be diluted): 2 mEq/mL vials

Premixed intravenous bags are also available with various diluents, in several concentrations and sizes.

 

POTASSIUM PHOSPHATE: 1,350 mg of monobasic potassium phosphate is equivalent to 10 mEq (mmol) of potassium.


Tablet

K-Phos (U.S.): 500 mg (to be dissolved in liquid)

 

Indicated when phosphate deficit accompanies potassium depletion (e.g., diabetic ketoacidosis).3

Also used for the prevention and treatment of hypophosphatemia.3

Injectable solution is considered a high-alert medication by ISMP.6

 

Injectable solution

Generics (must be diluted): 3 mmol/mL, 1.29 mmol/mL (Canada)

POTASSIUM BICARBONATE: 1,000 mg of potassium bicarbonate is equivalent to 10 mEq (mmol) of potassium.


Capsule

 

K-Bicarb (U.S., OTC): 99 mg

Can be considered in patients with hypokalemia and metabolic acidosis due to its alkalinizing effect.3,4

 

Effervescent tablet


Effer-K (U.S.): 10 mEq, 20 mEq, 25 mEq
Klor-Con EF (U.S.): 25 mEq

 

POTASSIUM GLUCONATE: 2,350 mg of potassium gluconate is equivalent to 10 mEq (mmol) of potassium.

 

Tablet

Generics (U.S., OTC): 99 mg, 550 mg, 595 mg
Generics (Canada): 50 mg, 99 mg, 100 mg, 595 mg

 

Considered a dietary supplement to prevent hypokalemia.4

Gluconate metabolizes to bicarbonate, so can be considered in patients with hypokalemia and metabolic acidosis.7

 

Extended-release tablet/caplet

Generics (U.S., OTC): 595 mg
Generics (Canada): 100 mg, 195 mg

 

POTASSIUM ACETATE: 975 mg of potassium acetate is equivalent to 10 mEq (mmol) of potassium.


Injectable solution

Generics (must be diluted): 2 mEq/mL (U.S.), 4 mEq/mL


Consider for treatment and prevention of hypokalemia if acidemia is also present.4

Alternative to potassium chloride when you want to avoid administering chloride.


POTASSIUM CITRATE: 1,075 mg of potassium citrate is equivalent to 10 mEq (mmol) of potassium.

 

Extended-release tablet

Urocit-K: 5 mEq, 10 mEq, 15 mEq (U.S.)
Generics: 5 mEq, 10 mEq, 15 mEq
K-Citra (Canada): 10 mEq

 

Generally used for management of renal tubular acidosis with calcium stones, uric acid kidney stones, or calcium kidney stones in patients with hypocitruria (low urinary citrate levels).8

K-Citra is recommended for treatment or prophylaxis of hypokalemia and to help reduce the formation of kidney stones.9

Can be considered in patients with hypokalemia and metabolic acidosis due to its alkalinizing effect.10

Some formulations produce a “ghost” tab in the stool (e.g., Urocit-K).11

 

Solution

K-Citra: 10 mEq/5 mL

Abbreviations: GI = gastrointestinal; ISMP = Institute for Safe Medication Practices; OTC = over-the-counter.

References

  1. National Association of Pharmacy Regulatory Authorities. National drug schedules. https://napra.ca/national-drug-schedules?letter=p&page=2. (Accessed December 7, 2020).
  2. Saleem F, Sharma A. Drug induced esophagitis. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing;2020-. 2020 June 23.
  3. Flurie RW. Disorders of potassium and magnesium homeostasis. In: DiPiro JT, Yee GC, Posey LM, et al, eds. Pharmacotherapy: A Pathophysiologic Approach. 11th ed. New York, NY: McGraw-Hill; 2020.
  4. Clinical Pharmacology powered by ClinicalKey. Tampa (FL): Elsevier; 2020. www.clinicalkey.com. (Accessed December 7, 2020).
  5. Lewis JL III. Hypokalemia. April 2020. http://www.merckmanuals.com/professional/endocrine_and_metabolic_disorders/electrolyte_disorders/hypokalemia.html. (Accessed December 9, 2020).
  6. ISMP. ISMP list of high-alert medications. 2018. https://www.ismp.org/sites/default/files/attachments/2018-08/highAlert2018-Acute-Final.pdf. (Accessed December 8, 2020).
  7. PubChem. Potassium gluconate. February 14, 2003. https://pubchem.ncbi.nlm.nih.gov/source/hsdb/3165. (Accessed December 8, 2020).
  8. Product information for Urocit-K. Mission Pharmacal. San Antonio, TX 78230. December 2019.
  9. Seaford Pharmaceuticals. K-Citra. https://seaford.ca/k-citra/. (Accessed December 8, 2020).
  10. National Kidney Foundation. dRTA: how is it treated? June 7, 2019. https://www.kidney.org/atoz/content/drta-how-it-treated. (Accessed December 8, 2020).
  11. Leslie S. Hypocitraturia and renal calculi. October 28, 2020. https://www.statpearls.com/ArticleLibrary/viewarticle/120007#ref_30139463. (Accessed December 8, 2020).

Cite this document as follows: Clinical Resource, Comparison of Potassium Salts. Pharmacist’s Letter/Prescriber’s Letter. February 2021. [370227]

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