Back

Electrolyte Imbalances

What Is It, Causes, Presentation, and More

Author: Nikol Natalia Armata

Editors: Alyssa Haag,Emily Miao, PharmD

Illustrator: Jessica Reynolds, MS

Copyeditor: Sadia Zaman, MBBS, BSc

Modified: 4 Dec 2023


What are electrolyte imbalances?

Electrolyte imbalances, also known as electrolyte disorders, refer to the variations of electrolyte levels within body fluids. Very high or very low levels of electrolytes disrupt the cell function by altering the cellular potential and can lead to various complications, some of which can be life-threatening.

Electrolytes are electrically charged minerals dissolved within the body fluids that, when exchanged properly in and out of the cells, preserve the body’s nerve and muscle functions. There are different types of electrolytes; sodium, potassium, and chloride play a significant role in cell homeostasis (i.e., a self-regulating process of the body to adjust to conditions that are optimal for survival), along with calcium, magnesium, phosphate, and bicarbonate. The prefixes hypo- and hyper- are used to describe the relative concentrations of any electrolyte in the extracellular fluid as low and high levels, respectively.  

What causes electrolyte imbalances?

Electrolyte imbalances are caused by different conditions and medications that intervene with the body’s natural fluid balance.

Sodium 

Hyponatremia is considered the most common electrolyte imbalance. It can be caused by the decrease of the circulating blood volume, as seen in congestive heart failure and hepatic cirrhosis. Additionally, disorders leading to high antidiuretic hormone (ADH) levels, like syndrome of inappropriate ADH secretion (SIADH), adrenal insufficiency, and hypothyroidism can also cause hyponatremia. Primary polydipsia  (i.e., excessive water intake), low dietary sodium intake causing an increase in blood volume, hyperglycemia, and dyslipidemia are all causes of hyponatremia. Hypernatremia, on the other hand, is usually caused by unreplaced fluid loss through the skin and gastrointestinal (GI) tract (e.g., excessive sweating, vomiting, or diarrhea), overload of hypertonic saline, medications (e.g. lithium), and rarely, following excessive physical activity that causes water to shift into cells.

Potassium

Hypokalemia is usually caused by low dietary intake or unreplaced fluid loss from the GI tract and urine and can be seen after excessive vomiting and loop diuretic use, respectively. Hyperkalemia can be noted in metabolic acidosis states - this is due to extensive potassium release from cells - but can also be noted in insulin deficiency, diabetic ketoacidosis, beta-blocker use, or following cell death in chemotherapy, where intracellular stores are released. Decreased potassium excretion from the kidneys (e.g. in acute or chronic kidney disease), aldosterone deficiency, or aldosterone resistance can also cause increased potassium levels. 

Chloride

Hypochloremia is mostly encountered after great GI fluid losses, as well as in renal fluid losses with diuretics. Hyperchloremia can occur when fluid losses exceed chloride losses; when the body’s ability to manage excessive chloride is disrupted; or when the bicarbonate serum levels are low and chloride levels are high. Normal anion gap metabolic acidosis or respiratory alkalosis may be present with low bicarbonate levels and hyperchloremia. 

Bicarbonates

Bicarbonate levels shift in acid-base disturbances. There is an increase in bicarbonate levels in primary metabolic alkalosis and it acts as compensation in primary respiratory acidosis. Bicarbonate falls in both primary metabolic acidosis and also decreases in response to primary respiratory alkalosis.

Calcium 

Hypocalcemia can be caused by hypoparathyroidism, typically seen post-surgery after thyroidectomy (i.e., after thyroid removal) due to frequent accidental damage due to their proximity to the thyroid. Hypocalcemia can also be noted in severe vitamin D deficiency, due to malnutrition or malabsorption. Hypercalcemia can be seen in individuals with malignancies, hyperparathyroidism, or in those prescribed thiazide diuretics or lithium. 

Magnesium

Hypomagnesemia can be seen after renal or GI fluid losses, and more rarely in individuals who consume excessive amounts of alcohol. Hypermagnesemia can occur after increased magnesium intake, either orally (e.g., after use of magnesium-containing medications such as antacids and laxatives) or more commonly through intravenous access. 

Phosphate

Low levels of phosphate in the blood can be seen in individuals with vitamin D deficiency, hyperparathyroidism, and refeeding syndrome, which is a potentially fatal condition that causes unexpected shifts of fluids and electrolytes in malnourished individuals following re-introduction of food. Hyperphosphatemia, on the other hand, can be caused by hypoparathyroidism and chronic kidney disease.

Excited Mo character in scrubs
Join millions of students and clinicians who learn by Osmosis!
Start Your Free Trial

What are the signs and symptoms of electrolyte imbalance?

Electrolyte imbalances have a very broad range of signs and symptoms, from being completely asymptomatic to having fatal arrhythmias. The coexistence of one or more electrolyte imbalances in individuals with mixed medical conditions can create a complex clinical presentation. However, typically, each electrolyte imbalance presents with signs and symptoms that are more indicative of the specific imbalance. 

Hyponatremia, for example, has neurological manifestations, presenting with headaches, confusion, nausea, or delirium (i.e., mental disturbance characterized by confusion and disrupted attention, disordered speech, and hallucinations). Especially if hyponatremia presents acutely, from a rapid overcorrection of hypernatremia, osmotic demyelination syndrome can occur causing cerebral edema. Individuals with hypernatremia, on the other hand, may be agitated and unable to sleep or rest. Hypernatremia might affect their heart and respiratory rate, due to the reduction of the extracellular fluid volume, causing tachycardia or tachypnea. Both imbalances of potassium, hypokalemia and hyperkalemia, have muscle-related symptoms, such as muscle weakness and cramping; these can also affect the cardiac muscle and cause arrhythmias. Hypokalemia can also cause constipation, whereas hyperkalemia can lead to abdominal pain or diarrhea. 

Disturbances of calcium levels present with vague symptoms of weakness, nausea, cramping. Hypocalcemia can present with the Trousseau sign; this is characterized by involuntary contraction of the muscles in the hand and wrist after the compression of the upper arm with a blood pressure cuff;  and the Chvostek sign, which is characterized by spasm of the facial muscles when gently tapping an individual's cheek, in front of the ear. Magnesium depletion may also return positive Trousseau’s and Chvostek’s signs and should be suspected in lethargic individuals presenting with tremor or personality changes. Hypomagnesemia is frequently associated with hypokalemia, therefore while trying to correct the electrolyte imbalances management of the hypomagnesemia may proceed hypokalemia treatment. Hypermagnesaemia is mostly associated with decreased consciousness, confusion, muscular weakness, and the absence of reflexes

Any imbalance of phosphate levels usually causes muscle cramping, weakening, and numbness, and can also affect bone density, resulting in softened or weakened bones. Bicarbonate disturbances often present with headaches, fatigue, and any other symptoms related to the underlying acid-base disturbance. Imbalances of chloride are mostly asymptomatic. In cases of extremely high or extremely low levels of chloride, vague symptoms, such as confusion or swelling, may be noticed. 

How is an electrolyte imbalance diagnosed?

In order to diagnose any electrolyte imbalance, a thorough review of medical and personal history is often necessary. Additional information obtained by relatives can also be helpful if the individual is not mentally capable of answering questions (e.g., with hyponatremia). Notably, review of medications prescribed (e.g., diuretics like furosemide, or antibiotics like amphotericin B) is key to diagnosis, as they are frequently the cause of electrolyte imbalances. Measurement of electrolyte levels in the blood, available through a comprehensive metabolic panel blood test,  is also necessary for diagnosis confirmation. An arterial blood gas (ABG) test may also be ordered to determine the acid-base status. Mixed electrolyte, acid-base, and fluid disturbances occur frequently and can be challenging to diagnose due to their complex clinical presentation. 

How is an electrolyte imbalance treated?

Each electrolyte imbalance requires a different approach in order to be treated. Treatment of the underlying cause is the most effective way to restore the electrolytes to their expected values. Intravenous fluid administration and replacement of any needed electrolyte may be helpful. Minor electrolyte disturbances can be corrected with small dietary changes, like eating more fruits and vegetables or drinking a sports drink to increase hydration and restore electrolyte balance. The rate at which the imbalance is corrected should always be monitored, as there may be significant consequences for the individual. For example, rapid correction of hypernatremia can cause cerebral edema

What are the most important facts to know about electrolyte imbalances?

Electrolyte imbalances are variations of the electrolyte levels, which are electrically charged molecules that preserve the body’s function. Consequently, any imbalance can cause a very broad range of symptoms, from confusion, muscle weakening, and fatigue to personality changes, reflex alterations, and fatal arrhythmias. Diagnosis is based on history, clinical presentation, and blood tests, whereas treatment depends on the underlying cause. 

Quiz yourself on Electrolyte Imbalances

10 Questions available

Quiz now!

Watch related videos:

Mo with coat and stethoscope

Want to Join Osmosis?

Join millions of students and clinicians who learn by Osmosis!

Start Your Free Trial

Related links

Electrolyte disturbances: Pathology review
Hyperkalemia: Clinical practice
Phosphate, calcium and magnesium homeostasis
Acid-base disturbances: Pathology review
Hydration

Resources for research and reference

Balcı, A. K., Koksal, O., Kose, A., Armagan, E., Ozdemir, F., Inal, T., & Oner, N. (2013). General characteristics of patients with electrolyte imbalance admitted to emergency department. World Journal of Emergency Medicine, 4(2), 113–116. DOI: 10.5847/wjem.j.issn.1920-8642.2013.02.005

National Kidney Foundation. (2021, February 11). Metabolic acidosis. In National Kidney Foundation. Retrieved September 17, 2021, from https://www.kidney.org/atoz/content/metabolic-acidosis.  

Nardone, R., Brigo, F., & Trinka, E. (2016). Acute symptomatic seizures caused by electrolyte disturbances. Journal of Clinical Neurology, 12(1), 21. DOI: /10.3988/jcn.2016.12.1.21  

Sahay, M., & Sahay, R. (2014). Hyponatremia: A practical approach. Indian Journal of Endocrinology and Metabolism, 18(6), 760–771. DOI: 10.4103/2230-8210.141320 

Shrimanker I, Bhattarai S. (2021, Jul 26).  Electrolytes. In: StatPearls [Internet]. Retrieved from: https://www.ncbi.nlm.nih.gov/books/NBK541123/

Weiss-Guillet, E. M., Takala, J., & Jakob, S. M. (2003). Diagnosis and management of electrolyte emergencies. Best practice & research. Clinical Endocrinology & Metabolism, 17(4), 623–651. DOI: 10.1016/s1521-690x(03)00056-3