When it occurs, symptoms may not appear until magnesium levels are incredibly high.
How Much Magnesium Do You Need?
How Much Is Too Much?
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If you are taking magnesium supplements, the tolerable upper levels are lower than the maximum daily allowance.
This is because the recommended daily allowance includes magnesium from all sources, including food.
Tolerable upper levels for magnesium supplements are as follows:
Is 500 mg of magnesium too much?
Five hundred milligrams of magnesium is above the amount considered tolerable for an adult.
If you are taking magnesium supplements, you should limit your daily intake to 350 mg or less.
Magnesium is widely available in plant and animal food sources.
Supplements and Medications
You should talk to your healthcare provider before starting a supplement.
Do not take more than the recommended daily amounts.
Risk Factors
Magnesium toxicity is rare because your kidneys help rid the body of excess magnesium.
People who take laxatives and antacids for extended periods may have an increased risk for hypermagnesemia.
While rare, such excessive amounts of magnesium in the body could be fatal.
Dialysis is a process of removing excess water and toxins from the kidneys.
A registered dietitian can work with you to create an eating pattern that contains enough magnesium.
If you are considering a magnesium supplement, chat with your doctor first.
Summary
Magnesium overdose is rare.
When it occurs, symptoms can include diarrhea, nausea and vomiting, facial flushing, and headache.
You cannot overdose on magnesium from diet.
Severe hypermagnesemia could be fatal in someone with a kidney disorder.
However, early treatment can improve outcomes.
Treatment includes stopping supplements, intravenous calcium gluconate, diuretics, and dialysis in people with impaired kidney function.
Office of Dietary Supplements.Magnesiumfact sheet for health professionals.
Office of Dietary Supplements.Magnesium consumer.
Al Alawi AM, Majoni SW, Falhammar H.Magnesium and human health: Perspectives and research directions.Int J Endocrinol.
2018;2018:9041694. doi:10.1155/2018/9041694
Razzaque MS.Magnesium: Are we consuming enough?Nutrients.
2018;10(12):1863. doi:10.3390/nu10121863
MedlinePlus.Magnesium hydroxide.
Mylanta.Mylanta products ingredients and dosage.
Chan School of Public Health.Magnesium.
2017;17(1):241. doi:10.1186/s12884-017-1424-3
UpToDate.Hypermagnesemia: Causes, symptoms, and treatment.
