eMedicine Specialties > Emergency Medicine > Endocrine & Metabolic

Hypokalemia: Treatment & Medication

Author: David Garth, MD, Attending Physician, Department of Emergency Medicine, Mary Washington Hospital
Contributor Information and Disclosures

Updated: Apr 2, 2010

Treatment

Prehospital Care

  • Be attentive to the ABCs.
  • If the patient is severely bradycardic or manifesting cardiac arrhythmias, appropriate pharmacologic therapy or cardiac pacing should be considered.

Emergency Department Care

  • Patients in whom severe hypokalemia is suspected should be placed on a cardiac monitor; establish intravenous access and assess respiratory status.
  • Direct potassium replacement therapy by the symptomatology and the potassium level. Begin therapy after laboratory confirmation of the diagnosis.
  • Patients who have mild or moderate hypokalemia (potassium level of 2.5-3.5 mEq/L) are usually asymptomatic; if these patients have only minor symptoms, they may need only oral potassium replacement therapy. Patients with mild hypokalemia whose underlying cause of hypokalemia can be corrected may not need any potassium replacement, such as those with vomiting successfully treated with antiemetics. If cardiac arrhythmias or significant symptoms are present, then more aggressive therapy is warranted. This treatment is similar to the treatment of severe hypokalemia.
  • If the potassium level is less than 2.5 mEq/L, intravenous potassium should be given. Admission or ED observation is indicated; replacement therapy takes more than a few hours.
  • The serum potassium level is difficult to replenish if the serum magnesium level is also low. Look to replace both.

Consultations

An internist or a nephrologist should be consulted for admission or follow-up care.

Consider psychiatric consultation in laxative abuse, anorexia, or bulimia cases.9

Medication

Oral is the preferred route for potassium repletion because it is easy to administer, safe, inexpensive, and readily absorbed from the GI tract. For patients with mild hypokalemia and minimal symptoms, oral replacement is sufficient. For patients who have severe hypokalemia and are symptomatic, both intravenous and oral replacement are necessary. While intravenous potassium dosages of up to 40 mEq/h have been advocated, patients should receive no more than 20 mEq/h IV to avoid potential deleterious effects on the cardiac conduction system. Potassium solutions should never be given as an intravenous push and should be administered as a dilute solution. Higher concentrations of intravenous potassium are damaging to the smaller peripheral veins.

Electrolyte supplements

Potassium is essential for transmission of nerve impulses, contraction of cardiac muscle, maintenance of intracellular tonicity, skeletal and smooth muscles, and maintenance of normal renal function. These agents increase the body's potassium level. In general, 1 mEq/L drop in potassium correlates to a loss of 100-200 mEq of total body potassium. Hypokalemia may result from the movement of potassium into cells without loss of potassium from the body.


Potassium chloride (Klor-Con, K-Dur)

Potassium depletion sufficient to cause 1 mEq/L drop in serum potassium requires a loss of about 100-200 mEq of potassium from total body store.
Available in liquid, powder, or tablet form. Any form may irritate the stomach and cause vomiting. Should be taken with food or after meals to minimize GI discomfort.
Oral potassium preparations include 8 mEq KCI slow-release tablets, 20 mEq KCI elixir, 20 mEq KCI powder, 25 mEq KCI tablet.
In the symptomatic patient with severe hypokalemia, administer up to 40 mEq/h of the IV preparation. Maintain close follow-up care, provide continuous ECG monitoring, and check serial potassium levels.
Higher dosages may increase risk of cardiac complications. Many institutions have policies that limit maximum amount of potassium that can be given per hour.

Adult

20-40 mEq PO bid/qid; not to exceed 40 mEq PO/dose
Alternatively, 10-20 mEq/h IV via peripheral or central line

Pediatric

1-4 mEq/kg/24 h PO divided bid/qid
Alternatively, 0.5-1 mEq/kg/dose over 1 h; not to exceed adult maximum dose

Concurrent ACE inhibitors may elevate serum potassium concentrations; concurrent potassium-sparing diuretics or potassium-containing salt substitutes can produce severe hyperkalemia; in patients taking digoxin, hypokalemia may result in digoxin toxicity—caution if discontinuing potassium administration in patients maintained on digoxin

Hyperkalemia; renal failure; conditions in which potassium is retained; oliguria or azotemia; crush syndrome; severe hemolytic reactions; anuria; adrenocortical insufficiency

Pregnancy

A - Fetal risk not revealed in controlled studies in humans

Precautions

Caution in cardiac disease and renal impairment; plasma levels do not necessarily reflect tissue levels
When administering IV, do not infuse rapidly; high plasma concentrations of potassium may cause death due to cardiac depression, arrhythmias, or arrest; plasma levels do not necessarily reflect tissue levels; monitor potassium replacement therapy whenever possible by continuous or serial ECGs; when concentration >40 mEq/L infused, local pain and phlebitis may occur

More on Hypokalemia

Overview: Hypokalemia
Differential Diagnoses & Workup: Hypokalemia
Treatment & Medication: Hypokalemia
Follow-up: Hypokalemia
Multimedia: Hypokalemia
References
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References

  1. [Guideline] ECC Committee, Subcommittees and Task Forces of the American Heart Association. 2005 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care. Circulation. Dec 13 2005;112(24 Suppl):IV1-203. [Medline]. [Full Text].

  2. Latronico N, Shehu I, Seghelini E. Neuromuscular sequelae of critical illness. Curr Opin Crit Care. Aug 2005;11(4):381-90. [Medline].

  3. Ingram TC, Olsson JM. In brief: hypokalemia. Pediatr Rev. Sep 2008;29(9):e50-1. [Medline].

  4. Seigel JD, Di Palma JA. Medical treatment of constipation. Clin Colon Rectal Surg. 2005;18(2):76-80.

  5. Reactions Weekly. Dextrose: First report of ventricular arrhythmia: case report. Reactions Weekly. 2005;1046:11.

  6. Greenfeld D, Mickley D, Quinlan DM, Roloff P. Hypokalemia in outpatients with eating disorders. Am J Psychiatry. Jan 1995;152(1):60-3. [Medline]. [Full Text].

  7. Goldberger ZD. Images in cardiovascular medicine. An electrocardiogram triad in thyrotoxic hypokalemic periodic paralysis. Circulation. Feb 13 2007;115(6):e179-80. [Medline].

  8. [Guideline] Assadi F. Diagnosis of hypokalemia: a problem-solving approach to clinical cases. Iran J Kidney Dis. Jul 2008;2(3):115-22. [Medline].

  9. Becker AE, Grinspoon SK, Klibanski A, Herzog DB. Eating disorders. N Engl J Med. Apr 8 1999;340(14):1092-8. [Medline].

  10. Cohn JN, Kowey PR, Whelton PK, Prisant LM. New guidelines for potassium replacement in clinical practice: a contemporary review by the National Council on Potassium in Clinical Practice. Arch Intern Med. Sep 11 2000;160(16):2429-36. [Medline].

  11. Dominiczak AF, Semple PF, Fraser R, Lever AF, Wallace AM. Hypokalaemia in alcoholics. Scott Med J. Aug 1989;34(4):489-94. [Medline].

  12. Gennari FJ. Hypokalemia. N Engl J Med. Aug 13 1998;339(7):451-8. [Medline].

  13. Halperin ML, Kamel KS. Potassium. Lancet. Jul 11 1998;352(9122):135-40. [Medline].

  14. Howes LG. Which drugs affect potassium?. Drug Saf. Apr 1995;12(4):240-4. [Medline].

  15. Kleinfeld M, Borra S, Gavani S, Corcoran A. Hypokalemia: are elderly females more vulnerable?. J Natl Med Assoc. Nov 1993;85(11):861-4. [Medline].

  16. Küng M. Parenteral adrenergic bronchodilators and potassium. Chest. Mar 1986;89(3):322-3. [Medline].

  17. Mandal AK. Hypokalemia and hyperkalemia. Med Clin North Am. May 1997;81(3):611-39. [Medline].

  18. Paice BJ, Paterson KR, Onyanga-Omara F, Donnelly T, Gray JM, Lawson DH. Record linkage study of hypokalaemia in hospitalized patients. Postgrad Med J. Mar 1986;62(725):187-91. [Medline].

  19. Singhal PC, Venkatesan J, Gibbons N, Gibbons J. Prevalence and predictors of rhabdomyolysis in patients with hypokalemia. N Engl J Med. Nov 22 1990;323(21):1488. [Medline].

  20. Walters EG, Barnes IC. A survey of hypokalaemia in patients of general practitioners. Br J Clin Pract. May 1988;42(5):192-5. [Medline].

  21. Zull DN. Disorders of potassium metabolism. Emerg Med Clin North Am. Nov 1989;7(4):771-94. [Medline].

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Further Reading

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Keywords

hypokalemia, low potassium, potassium level less than 3.5 mEq/L, potassium homeostasis, palpitations, skeletal muscle weakness, cramping, paralysis, paresthesias, abdominal cramping, ventricular arrhythmias, premature atrial beats, premature ventricular beats, respiratory distress, hypoventilation, respiratory failure, lethargy, fasciculations, tetany, hyperaldosteronism, magnesium depletion, ileal loop, diuretics, alkalosis, decreased tendonreflexes, cushingoid appearance

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Contributor Information and Disclosures

Author

David Garth, MD, Attending Physician, Department of Emergency Medicine, Mary Washington Hospital
David Garth, MD is a member of the following medical societies: American Academy of Emergency Medicine and American College of Emergency Physicians
Disclosure: Nothing to disclose.

Medical Editor

Robin R Hemphill, MD, MPH, Associate Professor, Director, Quality and Safety, Department of Emergency Medicine, Emory University
Robin R Hemphill, MD, MPH is a member of the following medical societies: American College of Emergency Physicians and Society for Academic Emergency Medicine
Disclosure: Nothing to disclose.

Pharmacy Editor

Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine
Disclosure: eMedicine Salary Employment

Managing Editor

Howard A Bessen, MD, Professor of Medicine, Department of Emergency Medicine, UCLA School of Medicine; Program Director, Harbor-UCLA Medical Center
Howard A Bessen, MD is a member of the following medical societies: American College of Emergency Physicians
Disclosure: Nothing to disclose.

CME Editor

John D Halamka, MD, MS, Associate Professor of Medicine, Harvard Medical School, Beth Israel Deaconess Medical Center; Chief Information Officer, CareGroup Healthcare System and Harvard Medical School; Attending Physician, Division of Emergency Medicine, Beth Israel Deaconess Medical Center
John D Halamka, MD, MS is a member of the following medical societies: American College of Emergency Physicians, American Medical Informatics Association, Phi Beta Kappa, and Society for Academic Emergency Medicine
Disclosure: Nothing to disclose.

Chief Editor

Erik D Schraga, MD, Staff Physician, Department of Emergency Medicine, Mills-Peninsula Emergency Medical Associates
Disclosure: Nothing to disclose.

 
 
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