What Are The Symptoms Of High Magnesium Levels?

What Are The Symptoms Of High Magnesium Levels? Muscle weakness. Fatigue. Nausea and vomiting. Trouble breathing. Cardiac arrest, the sudden stopping of the heart (in severe cases) What are the signs of magnesium sulfate toxicity? Symptoms of magnesium sulfate toxicity are seen with the following maternal serum concentrations: loss of deep tendon reflexes (9.6-12 mg/dL)