The Effects of Low Sodium in the Elderly

Doctor speaking with an elderly woman.
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Changes in the way your body processes water can affect your balance of fluids and electrolytes as you age. Taking diuretics, pain medication, antidepressants or other prescription drugs may also alter your fluid balance. Symptoms of low sodium may not appear until your blood sodium level has fallen to a dangerous point, according to an article in the June 15, 2000 issue of "American Family Physician." Although certain behavioral or cognitive changes may point to a low sodium level, the only way to confirm that you have low sodium, or hyponatremia, is through blood tests. Having your sodium levels checked regularly by your doctor should be a routine part of your medical care.

Confusion, Disorientation and Drowsiness

Neurological changes are among the first signs of low sodium, an electrolyte that affects your fluid volume, nerve and muscle function. Confusion, disorientation and drowsiness--common symptoms of low sodium--may masquerade as the symptoms of other neurological conditions in the elderly, such as vascular dementia or Alzheimer's disease. If you live in a long-term care facility or you've been hospitalized, you may be especially prone to low sodium levels due to changes in your daily routines. Ongoing confusion and low energy levels may be signs that you have chronically low sodium. Monitoring your fluid intake and your cognitive status are important aspects of your care.


Nausea and Malaise

Nausea may be a sign of a low sodium level. If you've been sick or have had reactions to medications that caused vomiting or diarrhea, you may have lost sodium as a result. Drinking too much water to compensate for your loss of fluids can contribute to low sodium levels. Ongoing malaise--a general sense of physical discomfort--may be a sign that your sodium level is chronically low.


Your heart function affects the volume of fluids in your body. Heart disease may lead to low blood sodium levels. Liver failure may also affect the amount of sodium in your bloodstream. Headaches caused by the buildup of fluid in your brain tissues are a common symptom of hyponatremia. However, you may not experience headaches until your blood sodium level has dropped to a very low level. Headaches may be a sign of severe hyponatremia or another serious medical condition and warrant prompt medical attention.


Restlessness and Twitching

In the elderly, alterations in kidney function can affect the way your body concentrates urine and processes sodium. Sodium is an electrolyte, a compound that conducts electrical signals to your nerves and muscles. In the late stages of hyponatremia, you may have twitching, restlessness and other signs that your nervous system has been affected. Symptoms of low sodium can develop rapidly once your sodium levels drop.

Coma and Respiratory Arrest

Severe hyponatremia may cause a loss of consciousness and respiratory function. The brain can swell quickly when sodium levels drop too low. Severe hyponatremia is an emergency medical condition that requires immediate intervention to restore your fluid and electrolyte balance.



To maintain a healthy balance of fluids and sodium, your doctor may recommend changes in any medications you may be taking that affect your sodium levels. You may also need to reduce your fluid intake or increase the amount of salt you consume. Consult your doctor for a complete medical evaluation if you've had recent changes in your mental status, energy levels, nerve function or thirst.