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Definition
By Mayo Clinic staffHyponatremia is an abnormally low concentration of sodium in your blood.
When your blood sodium is too low, your cells malfunction — causing swelling. In chronic hyponatremia, sodium levels drop gradually over several days or weeks — and symptoms are typically moderate. In acute hyponatremia, sodium levels drop rapidly — resulting in potentially dangerous effects, such as rapid brain swelling, which can result in coma and death.
Hyponatremia occurs when the sodium in your blood is diluted by excess water. Hyponatremia may result from medical conditions that impair excretion of water from your body, or by a significant increase in water consumption, such as by athletes competing in marathons and other high-endurance events.
Treatment focuses on the underlying condition and may include intravenous fluids and medications.
Symptoms
