Table of ContentsView AllTable of ContentsSymptomsCausesDiagnosisTreatmentComplications of Low Sodium Levels
Table of ContentsView All
View All
Table of Contents
Symptoms
Causes
Diagnosis
Treatment
Complications of Low Sodium Levels
Hyponatremiameans the concentration ofsodiumin your blood is lower than what is needed for key functions like normalblood pressure, muscle contractions, and nerve signals in your body.Recovery time from low sodium levels will vary with the cause, symptoms, and severity, but healthcare providers target the first six hours for treatment.
This article takes a closer look at the symptoms and causes of hyponatremia and explains how the condition is diagnosed and treated.
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Symptoms of Low Sodium Levels
While people with mild hyponatremia often have no symptoms, the likelihood of them occurring increases the more that sodium levels drop.
Common signs and symptoms of low sodium include:
What Causes Hyponatremia?
Sodium is an essential mineral and most people in the United States have too much of it in their diet, making acute or chronic hyponatremia uncommon.Hyponatremia can occur due to diet and lifestyle factors or medical conditions that affect the balance of water and sodium in the body.
Types of Hyponatremia
There are three main types of hyponatremia, reflecting the different ways that your body can have too little sodium, too much water, or both that lead to dilutional hyponatremia.They describe fluid status and are called:
How Much Sodium You Need Per Day
Lifestyle Factors
Excessive sweating can cause the rapid loss of sodium. Humidity and environmental factors can contribute to the risk.Sweatand other body fluids are high in sodium. If you are unable to properly replenish sodium supplies after heavy sweating, sodium levels can drop precipitously.
If youdrink excessive amounts of waterafter sweating without replacingelectrolytes(essential minerals like sodium, calcium, and potassium), sodium levels are diluted and can drop even further.Overhydrationfurther increases the risk. You also may need to consume more salt.
Medical Causes
There are medical conditions that can cause hyponatremia. Some develop slowly over time with symptoms developing gradually. Others develop rapidly with symptoms developing abruptly.
Medical causes of hyponatremia include:
Hyponatremia is diagnosed with a physical exam, lab tests, and a review of your medical history. Central to the diagnosis is a blood test that measures the concentration of sodium in your blood.
The levels are measured in milliequivalents per liter (mEq/L) and classified as follow:
The physical exam and medical history provide clues as to the underlying cause. Tests will check for abnormalities in your blood pressure, urine volume, and urine concentration. Other blood tests may look for abnormalities in your adrenal hormone levels or liver function.
Your healthcare provider will also check for neurological (nervous system-related) problems such as a loss of alertness, concentration, or orientation.
What Is a Dangerously Low Sodium Level?Severe hyponatremia is defined as under 120 to 125 mEq/L.Symptoms can be absent and then progress from mild nausea and vomiting to headaches, muscle cramps, and mental confusion. If untreated, serious complications can include seizures, coma, and brain swelling.
What Is a Dangerously Low Sodium Level?
Severe hyponatremia is defined as under 120 to 125 mEq/L.Symptoms can be absent and then progress from mild nausea and vomiting to headaches, muscle cramps, and mental confusion. If untreated, serious complications can include seizures, coma, and brain swelling.
Sodium Blood Test: What to Expect
Recovering from Low Sodium Levels
The treatment of hyponatremia can be simple at times and challenging at others. Generally, the focus is on managing the underlying cause while slowly restoring sodium and fluid balance in the first six hours of treatment, though it may take days or longer in chronic, complicated cases.
Dietary Intake
If a low-salt diet is the cause of your hyponatremia, your healthcare provider will recommend slowly increasing your salt intake. The recommended sodium intake is around 1 teaspoon of salt per day for adults and 1/2 teaspoon of salt per day for children.
You will also be advised to drink enough water—around 12 cups per day for females and 16 cups per day for males—but not to overhydrate.
Your healthcare provider can discuss dietary changes that are meant to prevent future episodes of hyponatremia. Keep in mind that the salt in processed foods, bread, pasta, sauces, and even desserts counts toward the daily recommended intake.
How to Reduce Salt in Your Diet
Intravenous Sodium Replacement
The medical team will restore the sodium level over the course of several hours or days, depending on the severity of your condition. They then can move forward in addressing and treating any underlying cause to ensure your best chances of recovery.
Risks of IV Sodium ReplacementThe intravenous replacement of sodium needs to be done gradually. If delivered too quickly, sodium can damage the protective coating around nerves cells in the brain, referred to asosmotic demyelination. This can lead to long-lasting and even permanent brain injury.
Risks of IV Sodium Replacement
The intravenous replacement of sodium needs to be done gradually. If delivered too quickly, sodium can damage the protective coating around nerves cells in the brain, referred to asosmotic demyelination. This can lead to long-lasting and even permanent brain injury.
Medications
There are few medications that are consistently effective in treating hyponatremia.
Drugs called vasopressin receptor antagonists are sometimes used in people who have fluid retention and avoided in those with low fluid volumes.These drugs work best in people with congestive heart failure, cirrhosis, and SIADH.
Declomycin (demeclocycline) is anantibioticsometimes used to treat SIADH.The results can vary, with some people experiencing an overcorrection of sodium levels. The drug can also cause kidney problems andphotosensitivity(sensitivity to the sun) in some.
Complications of Acute Hyponatremia
With acute hyponatremia, the rapid decline in blood sodium can lead to serious and sometimes irreversible health complications. Due to the rapid increase of fluids in the brain and other organs, a person with acute hyponatremia may experience:
Complications of Chronic Hyponatremia
Chronic hyponatremia tends to be less severe but is insidious because it can silently damage organs over time even at milder levels. Complications include:
Summary
Hyponatremia is abnormally low levels of sodium in the blood. It can be diagnosed with a blood test.
A person with hyponatremia will have no symptoms if sodium levels are mildly decreased. When sodium levels drop significantly, hyponatremia can cause headache, fatigue, nausea, vomiting, muscle cramps, and difficulty concentrating. Severe cases can lead to seizures, coma, kidney failure, and death.
Hyponatremia can have several causes, including severe diarrhea, no-salt diets, overhydration, use of diuretics, congestive heart failure, certain hormonal problems, and cirrhosis.
The treatment may involve increased salt intake for mild cases and intravenous sodium replacement for severe ones.
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