Magnesium Overdose

What is magnesium overdose?

Magnesium overdose is an excess of magnesium in the body. Magnesium is an essential mineral that helps muscles function and maintain energy. In the absence of kidney disease, your body naturally removes excess magnesium. A magnesium overdose, also called magnesium toxicity or hypermagnesemia, generally occurs when magnesium is ingested in large quantities in the form of a supplement, either as a pill or a liquid. It is very rare to experience a magnesium overdose by consuming foods that have naturally occurring magnesium in them, such as fruits and vegetables or nuts and whole grains.

Magnesium is commonly found in over-the-counter medications. It is often used as a laxative, so diarrhea after taking a magnesium-based laxative can be a mild symptom of magnesium overdose. Antacids also contain magnesium. A mild magnesium overdose is usually accompanied by temporary diarrhea and nausea.

People who have impaired kidney function are at the greatest risk for magnesium overdose. Even a moderate magnesium overdose may cause a drop in blood pressure in those with kidney disease. Other possible serious symptoms include difficulty breathing, muscle weakness, and mental confusion. Serious cases of magnesium overdose may cause cardiac arrest.

Seek immediate medical care (call 911) for serious symptoms of a magnesium overdose, including severe abdominal, pelvic, or lower back pain; chest pain or pressure; confusion or loss of consciousness for even a brief moment; rapid heart rate (tachycardia); and shortness of breath.