Hi, Brief answer: Very low sodium in the blood can cause a range of effects from nausea and dizziness to seizures, coma, and death so it is important to correct sodium to a normal level. Correction of very low sodium levels needs to be carried out under medical supervision to avoid damage to the brain. Detailed answer: Sodium is an electrolyte that is important for cells to function, live, and grow. Sodium is required for the body’s processes and functions, including water balance, blood pressure, nerve electrical signals, and muscle contraction. Low sodium levels in the blood (a condition called hyponatremia) can cause a range of effects from the less severe such as low blood pressure, dizziness, headache, and fatigue to the more severe including muscle weakness, irregular heart rhythms, seizure, coma, and death. Correcting sodium to a normal level level too quickly can cause damage to the brain cells and nerves, so it should be carried out under medical supervision. Giving saline IV is how doctors correct very low sodium levels due to many causes. Saline is a solution of salt (sodium chloride) in water at a concentration that matches the normal concentration of sodium in the blood. It is safe for patients to receive saline by IV. I have treated patients with low sodium levels with saline IV just as your doctor suggested. I encourage you to talk with your doctor about your low sodium level. Your doctor can also evaluate for what is causing your sodium level to be low. Hope I have answered your question. Let me know if I can assist you further. Take care. Regards, Dr. Aaron Shapiro, General & Family Physician