Hi,
The symptoms of a low blood serum include nausea and vomiting, headache, confusion, fatigue and loss of appetite. Also, restlessness, irritability and muscle weakness may be present. Muscle spasms, cramps and seizures may also occur.

The severity of the symptoms are related to the level of sodium. The lower the sodium, the more prominent the symptoms will be. The most serious symptoms involve the brain. The low sodium causes water to enter the brain. It may swell within the rigid skull and it then becomes squeezed and seizures may occur. The faster the sodium falls the more severe the symptoms will be. A low sodium that has occurred slowly may be reasonably well tolerated.

I hope this has helped you. If you have any further questions, please do not hesitate to contact me.
Regards,
Dr K A Pottinger
MBChB FRCA

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