Hyponatraemia - Complications

Authored by Dr Gurvinder Rull, 22 May 2017

Patient is a certified member of
The Information Standard

Reviewed by:
Dr Adrian Bonsall, 22 May 2017

Mild hyponatraemia leads to walking abnormalities in the elderly with a risk of falls and fractures. It can also lead to weaker bone structure making fractures more likely to occur after a fall. Mild hyponatraemia can also lead to memory problems and difficulty concentrating.

Sudden hyponatraemia can result in life-threatening complications as a result of sudden swelling of the brain (cerebral oedema), which can lead to coma and to fits (seizures), and which can be fatal.

Chronic hyponatraemia can also lead to cerebral oedema and permanent neurological changes - for example, seizures. The brain usually adapts to the slower fall in sodium so that brain swelling is not usually seen.

Too rapid correction of hyponatraemia can cause a condition called central pontine myelinolysis. Symptoms occur 2-4 days after onset and may present with paralysis of all four limbs (quadriplegia). This has been seen more often in those with alcohol dependency, female patients, those with low blood potassium levels (hypokalaemia), and patients who have had a liver transplant. If hyponatraemia is corrected at the appropriate rate these complications can be minimised.

Prevention of hyponatraemia

Advice to remain well hydrated and on use of electrolyte replacement solutions may help prevent hyponatraemia occurring in the setting of acute diarrhoea and/or being sick (vomiting), especially in the elderly and young.

Diuretics can lead to varying degrees of hyponatraemia. Patients should be warned of this potential side-effect and the symptoms that may occur. Also some patients may require blood tests to check sodium levels a few weeks after starting diuretics - for example, a patient who has had hyponatraemia before.

My condition, hypophosphatemia and oncogenic osteomalcia started about 3 years ago, however, was not diagnosed until six months ago. It started very gradually with body stiffness that over time...

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